CA1103823A - Automatic dialer having a recall memory - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
An automatic dialer for placing outgoing telephone calls from a facsimile terminal or the like in response to terminal and dialing control instructions read by a raster input scanner includes a recall memory and a display which allow an operator to account for calls that cannot be completed and to isolate the cause of that failure.

Description

38;~3 Il. BACKGROUND OF THE INVENTION
This invention relates to methods and means for utilizing raster input scanners as readers for automqtic telephone dialing equipment and, more particularly1 to automatic telephone diqling methods and means for facsimile sys~ems and the like.
Facsimile systems have gained widespread commercial acceptance because they offer rapid and accurate, long distance communication of most any type of graphic information (e.g., handwritten and printed pages, charts, graphs, and drawings), subject to minor exceptions which are principally attributable toresolution limitations. As is known, a basic facsimile system comprises a transmitting terminal and a receiving terminal which are interconnected by a communications link. Customarily, there is a raster input scanner within the transmitting terminal for sbrially convertina or remapping the two dimensional information content of an original document (generally called a "subject copy") into a corresponding, one dimensional video signal. Moreover, the transmitting terminal normally includes a modulator for modulating a suitable carrier signal in accordance with the video signal so that a passband signal is provided for transmission to the receiving terminal via the communications link. Accordingly~the receiving terminal typically has a demodulator for recovering the video signal and a raster output scanner for serially printing a more or less exact replica or "facsimile" of ~he subject copy in response to the video signal.
Dedicated transmitters and receivers are sometimes used as terminals for facsimile systems, but the more common practice is to employ transceivers which are selectively operable in a trqnsmit mode or a receive mode. As q general rule, the communications link or channel for facsimile communications is furnished on demand by a telephone dial system, such as the public switched telephone network.
Substantial effort and expense have been devoted to avtomating facsimile systems, thereby reducing the amount of operator intervention and supervision required. For example, the Xerox 200 Telecopier transceiver, which is

-2-32~
manufactured and sold by Xerox Corporation, operates essential~ly automatically, with the notable exception of bein~ able to place outgoing calls. Specifically, that unit automatically answers incoming calls and automatically disconnects incoming and outgoing calls. It can be auto-matically set in response to remotely generated commands to operate in a transmit mode or a receive mode at any one of its available document transmission rates of two, three, four and six minutes/page. Furthermore, the 200 transceiver includes an automatic document feeder which permits it to sequentially scan a plurality of subject copies automatic-ally when operating in a transmit mode. Additionally, there is a roll fed paper supply which permits that unit to auto-matically print successive facsimile copies when operating -in a receive mode. For a more detailed description of that transceiver, reference may be made to Mason et al. United States Patent No. 3,869,569, which issued March 9, 1~75 on a "Facsimile Transceiving Apparatus," and to Perreault et al. United States Patent No. 3,889,057, which issued June 10, 1975 on a "Facsimile Communication System."
General purpose automatic telephone dialers have been available for several years. Nevertheless, few, if any, facsimile terminals have been equipped wit~ auto-matic telephone dialing equipment prior to this invention. ~ -III. SUMMARY OF THE INVENTION
Against the foregoing background, an object of an aspect of the present invention is to provide methods and means for utilizing raster input scanners as readers for automatic telephone dialers. An object of an aspect of the invention is to provide methods and means for trans-lating raster scanned address indicia into the dial pulses or frequencies necessary to place outgoing telephone calls.

3-3;~
An object of an aspect of this invention is to provide economical methods and means for automatically placing outgoing telephone calls from unattended facsimile terminals. An ohject of an aspect of the invention is to provide methods and means for utilizing the raster input scanners of conventional facsimile transmitters and trans-ceivers as readers for automatic telephone dialing equipment.
An object of an aspect of the present invention is to provide methods and means for automatically placing outgoing telephone calls from unattended facsimile terminals at any preselected time of day, whereby those terminals can carry out facsimile communications at the most convenient time of day, such as during non-business hours when telephone traffic and charges are usually relatively low.
An object of an aspect of the present invention is to provide methods and means for automatically placing outgoing calls from unattended multi-speed facsimile terminals and for setting-up such terminals to operate in an individually preselected mode and at an individually preselected document transmission rate during each of those calls.
An object of an aspect of this invention lS to provide facsimile terminals with automatic dialing and -control equipment of the foregoing type, without impairing the existing ability of those terminals to function under manual or remote control.
In accordance with one aspect of this invention there is provided in combination with a telephone linked communications terminal having a raster input scanner, and an automatic dialer means for placing outgoing telephone calls from said terminal in response to dialing control , ~ ~ .

33~%3 instructions identified by mark sense indicia entered on address cards read by said scanner; the improvement compris-ing storage means for storin~ data identifying any jobs aborted by said automatic dialer means, and data generating means coupled between said scanner and said storaqe means Eor generating at least a part oE said data in response to a vicleo output signal supplied by said scanner whenever an address card is being scanned.
By way oE added explanation, a facsimile terminal is equipped with an automatic dialer which tempor-arily seizes control of the terminal when a unique recog-nition pattern at the leading edge of an address card is scanned. Each address card has a specially formatted instruction field which is divided into rows and columns to allow for the entry of mark sense indicia representing dialing and terminal control instructions. When a complete and unambiguous set of instructions are scanned, the dialer automatically makes a telephone call in accordance with the dialing and terminal control instructions. If the ~alI
cannot be completed or if the instructions are incomplete or unambiguous, the job is aborted and the terminal is returned to a standby state. If, on the other hand, the call is completed, communlcations are carried out in the usual way.
~25 Preferably, the facsimile ~erminal has an auto-matic document feeder so that one or more address cards and, if appropriate, one or more sets of subject copies may be preloaded into the feeder to be scanned on command. That command may be e~tered as a simple start instruction or as a delayed start -4a-~,, 1~: . r ' ~3~

instruction. If a delayed start is used, scanning is initiated by the automatic dia:Ler when the actual time of day comes into coincidence w.ith a preselected time of day for the delayed sta.rt.

IW. BRI~E' DESCRIPTION OF T~IE D~WINGS
Still u.rther objects and advantages oE the present invention will become apparent when the following detailed description is read in conjunction with the attached drawings, in which 1~ FIG. 1 is a simplified elevational view o~ a fac-simile transceiver which is equipped with an automatic tele-phone dialer constructed in accordance with the present invention;
FIG. 2 is a fragmentary elevational view, partially in section, of an automatic document feeder for the transceiver of FIG. l;
' FIG. 3 is another partially sectioned and fragmentary elevational view illustrating the optics included within the - -~
exemplary transceiver shown in FIG. l;
FIG. 4 second sheet of drawings diagrammatically illustrates a typical sequence of address cards, and subject copies as stacked in the input tray of the automatic document feeder shown in FIG. 2;
FIG. 4A is similar to FIG. 4 but pause cards are included;
FIG. SA is an enlarged front view of an address card; .
FIG~ 5B fourth sheet of drawings is an enlarged~
fragmentary view of a pause card;
P~G. 6 is an enlarged top plan view of the automatic telephone dialer shown in FIG l;

~,; f, :

38~3 FIG. 7 is a functional block diagram of the automatic dialer in com~ination wi-th the exemplary transceiver;
FIG. 8 is a diagram indicating the manner in which E'IGS. 9-16 are intented to be assembled;
5FIGS. 9-16 when assembled as indicated in FIG. 8, combine to form a more detailed block diagram of the automatic dialer in combination with the exemplary transceiver; and ~IGS. 17 and 18, when joined as indicated at AD, ~TN and AS, combine to form a Eunctional flow chaxt illustrat-10ing the basic operation of the automatic telephone dialer.
FIG. 19 is a flow chart expanding on the recall feature, - 5a -, ~
f :-3~;23 V. DETAILED DESCRIPTION OF THE ILLUSTRATED EMBOD!h~ENT
While the invention is described in some detail hereinbelow with specific reference to a single illustrated embodiment, it is to be understood that there is no intent to limi~ it to that embodiment. On the contrary, the aim is to cover ~11 rnodificq~ions, alternatives, and equivalents falling within the spirit and scope of the invention as defined by the appended clairns.
A. A Synergistic Environment Turning now to the drawings, ~nd at this point especiqlly to FIG. 1, there is an automatic telephone dialer 31 which is particularly well suited for use with a dedicated or non-dedicated facsimile terminal 32 having a raster input scanner 33 tFlG. 3). Indeed, there is synergism in that combination. Specifically, in keeping with one of the more important aspects of this invention, the automatic dialer 31 places outgoing telephone calls from the terminal 32 and conditions the terminal 32 for participation in facsimile communications in response to dialing and terminal controi instructions which are read into the dialer 31 by the input scanner 33 of the terminal 32. It has, in short, been recognized that the raster input scanner 33 of a more or less conventional facsimile transmitter or transceiver terminal 32 can advantageously be utilized as an instruction reader for the dialer 319 thereby avoiding the extra expense and complexity of having to furnish the dialer 31 with a separate reader.
As shown, the automatic dialer 31 comprises a hook switch 34 for supporting a telephone hqndset 35 and a keyboard 36 for manuclly entering dialing qnd dialer control instructions. Dialing instructions entered via the keyboard 36 are accepted and executed by the dialer 31 only if the handset 35 is "off hook",which indicates that the dialer 31 is being operated in a manual mode. All otherinstructions entered via the raster input scanner 33 and the keyboard 36 are accepted and executed while the handset 35 is "on-hook", thereby allowing the dialer 31 to perform in an automatic mode. For feeding raster scanned instructions and terminal status signals from the terminal 32 to the dialer 31 and for feeding 3û terminal control signals and dialing pulses or frequencies from the dialer 31 to the :
. .
.

~3823 terminal 32, there suitably is a multi-lead cable 37 coupled between the dialer 31 and the ~erminal 32.
In practice, the construction and operation of the automatic dialer 31 is unadvoidably dependent on the functional characteristics and compatability S requirements of ~he facsimile terminal 32. Therefore, an exemplary terminal 32 will be briefly reviewed to set the stage for a more detailed treatment of the dialer 31 .
To simplify this disclosure, the illustrated facsimile terminal 32 comprises a Xerox 2ûO Telecopier transceiver 38 which is interfaced with, say, the public switched telephone network by a standard data access arrangement 39 (FIG.7)9 such as a CBS IOOIF data coupler. A general familarity with the functional characteristics and the compatability requirements of that commercially available equipment is assumed. Consequently, the following discussion focuses on the features which are most relevant to the automatic dialer 31.
Preferably, the automatic dialer 31 supplements the facsimile terminal 32, whereby the existing capabilities of the terminal 32 are preserved. For example, the 200 Telecopier unit 38 is a half duplex facsimile transceiver which is selectively operable under local or remote control to function in a transmit mode or a receive mode at a document transmission rate of two, three, four or six minutes per standard 8Y2" x 11 " page. Moreover, the combination of that transceiver 38 with a suitable data access arrangement or DAA 39 provides the terminal with the ability to automatically answer incoming telephone calls and to automatically disconnect incom outgoing calls.
1. An Automatic Document Feeder Referring to FIG~ ~, the transceiver 38 has an automatic document feeder 41 (shown only in part) for serially feeding successive documents from aninput tray 42 to an output tray 43 (FIG~ 1) via a scan platen 44. As explained in additional detail in the aforementioned Mason et alO United States Patent No.
3,869, 569, the illustrated document feeder 41 has a bottom feeding, retard-type3û sheet separator 45 for separating the docurnents upstream of the scan platen 44.

.

~ ~ .

3~23 For that reason9 the documents to be scanned are loaded into the input tray 42 image side down and are stacked in consecutive order so that the first document is at the bottom of the stack and the last is at the top.
Concentr~ting for a moment on the sheet separator 45, there is a retard wheel 51 which is frictionally engaged wi~h an endless traction belt 52, therebyforming u feed nip 53 inboard of and slightly above the lead edge of the platen 44.
The input tray 42 is inclined downwardly toward the nip 53. Additionally, when afeed command is given, the truction belt 52 positively urges the bottommost document in the input tray 4~ into the feed nip 53. To that end, the traction belt 52 is extended through a slot (not shown) in the lead edge of the scan platen 44 and is trained around a drive wheel 54, an adjustable idler-type tension pulley 55, and an eccentric idler wheel 56. The eccentric 56 is radially aligned with a slot (also not shown) in the bottom of the input tray 42. Furthermore, the maximum and minimum radii of the eccentric 56, as supplemented by the finite thickness of the belt 52, are selected to be greater than and less than, respectively, the distance betwe~n the bottorn of the input tray 42 and a generally parallel axis of rotation for the eccentric 56.
When a feed command is given, the drive wheel 54 is rotatably driven (by means not shown) in the direction of the arrow. Sufficient tension is 2û maintained on the traction belt 52 to cause it to revoive in response to the rotation of the drive wheel 54, and that rotation is translated through the belt 52 to the tension pulley 55 and the eccentric 56. As a result of the rotation of the eccentric 56, the traction belt 52 is periodicaliy iifted through the slot in the bottom of the input tray 42 and brouaht into frictional engagement with the lower svrface or image side of the bottommost document in the input tray 42. Therefore, that document is positively urged into the feed nip 53 as the traction belt 52 continues to revolve. Any other documents in the input tray 42 are inhibited from enteringthe feed nip 53 because there is sufficient drag on the retard wheel 5i to prevent it from freely rotating. However, the rotation of the eccentric 56 periodically and3û alternately creates and releases u tension differential between the upper and lower . .

38~3 reaches of the traction belt 52. ~hen that differential is released or eqwlized, an impulse-lil<e force of sufficient magnitude to index the retard wheel 51 is generated. Hence, the wear surfqce of the retard wheel 51 (i.e., the surface in frictionql, sliding contact with the trqction belt 52) is periodicqlly advanced circumferentially thereby causing the retard wheel 51 to wear more or less uniformly.
In keeping with still further teqchings of the qbove-identified Mason et al. pqtent, the document feeder 41 suitably includes a series of feed rollers (not shown) downstream of the sheet separator 45 for feeding the successive documentsacross the scan platen 44. Those rollers and the drive wheel 54 of the sheet sepqrator 45 are typically driven in timed synchronism with the scanning cycle (described hereinbelow) of the transceiver 38 so that the docun ents enroute across the platen 44 are incrementally advanced a predetermined scan pitch distance during the flyback portion of each scanning cycle. If different scan pitches are to IS be accommodated, a factor common to all of the possible pitches is used as a basic step length, and the number of steps allotted to each scanning cycle is then controlled as a function of the selected scan pitch.
2. A Scanner/Printer Mechanisrn Turning to FIG. 3, the transceiver 38 has a iaser 61 and a scan mirror 62 which are alternatively and selectively utilized by the raster input scanner 33 and by a raster output scanner 63. This portion of the transceiver 38 is described in some detail in Mason United States Patent No. 3,870,816, which issued March 11, 1975 on an "Optical System for Transmit/Receive Mode Conditloning of Facsimile Transceivers" and which is here r~. Additionally, the aforementioned Perreault et al. and Mason et al. patents elaborate on the reiationship of the input and ou1put scanners 33 and 63 to the transceiver 38.
Reviewing the optics of the transceiver 38 on a functional level, it will be seen that the collimated light beam emitted by the laser 61 is reflected from a first corner mirror 64 to a second corner mirror 65 and then to the scqn mirror 62.
A galvanometer-type drive mechanism 66 cyclicaily rotates the scan mirror 62 _ g _ 38~3 back and forth through a predetermined planar scan angle, thereby periodically deflecting or sweeping the laser beam in a predetermined line scanning direction.
Downstreqm of the scan mirror 62 there is a flip mirror 67 which is selectively inserted into and removed from the optical path for the deflected laser beam so that the beam is alternatively routed to the raster input scanner 33 or the raster output scanner 63.
Unidirectional input scanning and output printing are achieved by synchronously blanking the laser 61 while the scan mirror 62 is counterrotating or flying back from an end of scan to a start of scan position. Preferably, the counterrotation of the scan mirror 62 is carried out at an appreciably higher angular velocity than the forward rotation so that only a relatively brief portion of each scanning cycle is consummed by the fly back period.
More particularly, when the transceiver 38 is operating in a transmit mode or a test mode, the flip mirror 67 is maintained in its solid line position (as `~ 15 shown in FIG. 3) to intercept and reflect the deflected laser beam from the scan mirror 62 to ~n elonaqted mirror 71 within the input scanner 33. During the forward rotation of the scan mirror 62, the laser 61 is excited to provide an output beam of constant intensity, and that beam is reflected from the mirror 71 to sweep across a line-like scanning station 72 on the scan platen 44. Hence, the documents to be scanned are illuminated in qccordance with a predetermined raster scanningpattern as they pass over the scanning station 72 in a direction generally perpendicular to the line scanning direction. To convert the two dimensional information content of the documents into a corresponding one dimensional video signal, there is a scan line length photodetector (not shown) for generating a video signal in response to the light which is diffusely reflected from the successively illuminated areas of the documents.
In contrast, when the transceiver 38 is operating in a receive mode, the laser 61 is modulated in accordance wlth an incoming video signal, and the flip mirror 67 is maintained in its phantom line position so that the defiected laserbeam passes from the scan mirror 62 to another elongated mirror 73 in the raster - lû -3~3 output scanner 63. Th laser beam reflected from the mirror 73 sweeps across a line-like printing station 74. Furthermore, the photoreceptor 75 of a xerographic processor 76 (shown only in part) is incrementally advanced past the printing station 74 during the fly back portion of each scanning cycle, at a rate dependent on the documen~ transmission time selected, and in a direction generally perpendicular to the line scanning direction. Consequently, the video modulated laser beam provided by the laser 61 exposes the photoreceptor 75 in accordance with a predetermined raster scanning pattern to create a latent electrostatic image of the facsimile copy. Of course, that copy is then usually printed through the use lû of standard xerographic printing techniques.
B. The Automatic Dialer .
Looking now to FIGS. 1-5, in keeping with this invention, the automatic dialer 31 is capable of executing dialing and terminal control instructions which are received from the raster input scanner 33 when address cards 81a - 81c bearing mark sense indicia representing those instructions are scanned. In practice, theaddress cards 81 a - 81 c and any associated subject copies 82 and 83 advantageously are loaded into the input tray 42 of the automatic document feeder 41 so that the scanning can be initiated on command.
1. An Address Card Format Focusing on FIGS. 3-5, the raster input æanner 33 makes no distinction between address cards 81 a - 81 c qnd ordinary subject copies 82 and 83. However, a distinctive bar code 84 is printed along the leading and trailing edge borders on the front and back of each of the address cards 81a - 81c (the bar codes 84 on the Ioading edge borders of the back and front of the address card 81b can be seen in FIGS. 4 and 5, respectively). Conseauently, whenever the input scanner 33 starts to scan one of the qddress cards 81 a - 8 Ic, a predetermined unique sea~uence of black and white (" I " and "0") picture elements is generated to signal the automatic dialer 31 that an address card is being scanned, even if the card happens to be inverted or upside down.
To accommodate mark sense indicia representing operator selected 3B~3 terminal control and dialing instructions~ there is an instruction field 85 comprising o plurality of orthogonal columns and rows on the front of each of the address cards 81a - 31c. As best sho~n in FIG. 5, the columns extend in the scan pitch direction and are eauidistantly spaced in the scqnning direction to distinguish between mutually exclusive instructions. The rows, on the other hand, extend in the scanning direction and are equidistantly spaced in the scan pitch direction to distinguish between successive, consistent instructions. Here, for example, the first or uppermost row is several columns wide to provide a selection of mutually exclusive terminGI control instructions calling for the transceiver 38 to operate in a transmit tsend) mode at a document transmission rate of two, three, four, or sixminutes per page or in a receive (polling) mode at a remotely determined document transmission rate. Next, there is a single column wide row which is dedicated to a dial tone instruction so that the automqtic dialer 31 initiates the dialing only after pausing for a predetermined time period or confirming that dial tone is being received, depending on whether blind dialing is selected or not as described hereinbelow. The following rows are each several columns wide to allow for identification of the digits (0-9) which are to be serially dialed and of the intermediate dial tones (-) which should be received while placing an outgoing telephone call to a predetermined, remote station.
As illustrated9 the address cards 31a - 81c are asymmetrical. They are properly oriented for reading only if they are presented to the input scanner 33front or instruction field side down and leading edge forward. Hence, if a misoriented address card is encountered by the input scanner 33, the automatic dialer 31 initiates a job abort process. That process is triggered whenever the automatic dialer 31 fails to receive instructions from the input scanner 33 within a predetermined period of time after detecting that an address card is being scanned.
A lapsed time decoding process is used by the automatic dialer 31 to identify or decode the instructions represented by the mark sense indicia èntered within tne instruction fields 85 of the address cards 81a - 81c. To that end, each row of the instruction field 85 is preceded at a preselected distance by another -~3~23 distinctive bar code 86 so that the input scanner 33 supplies the automatic dialer 31 with another predetermined, unique sequence of black and whlte picture elements upon reaching a predetermined point in the scanniny of eqch of those rows, thereby establishing a row-by-row timing reference for the autornatic dialer 31. The order, S spacing, and meaning of the poten~ial ins~ructions associated with the different rows of the instruction field 85 are Icnown, and the sweep velocity of the inputscanner 33 is also known. Therefore, the automatic dialer 31 decodes or identifies the selected instructions on the basis of the amount of time which passes during the scanning of each row of the instruction field 85 between the moment that the timing reference for that row is established and the moment that picture elemsnts are received to indicate that a mark representing a selected instruction is being scanned.
Instructions represented by appropriate mark sense indicia entered within successive rows of the instruction field 85 of an address card are accepted and executed by the automatic dialer 31, provided that one and only one instruction is marked for selection per row. If more than one instruction is so marked within any given row, all instructions from that row are rejected because there is an inherent ambiguity. If, on the other hand~ there are one or more intermediate rows of the instruction field 85 which have no instructions marked for selection, the2û automatic dialer 31 accepts, but does not execute, instructions represented by appropriate mark sense indicia entered in the subsequent rows because there is apotential ambiguity - viz., were the intermediqte rows simpiy skipped or were instructions inadvertentiy omitted?
Some skew of the address cards 81a - 8ic relative to the scanning station 72 of the input scanner 33 is normal and expected, especially when the automatic document feeder 41 or similar device is used. Thus, to ensure that theaddress cards 81 a - 81 c can be accurately reqd despite that skew, the printed bar codes 84 and 86 and the instruction representing mark sense indicia are preferably several times longer, as measured in the scan pitch direction, than the coarsestscan pitch of the input scanner 33.

~38Z~

2. A Keyboard/Display Unit for the Automatic Dia!er As shown in FIGS. I and 6, the keyboard 36 and a display 92 are employed for purposes of operator interaction with the automatic dialer.
Typically, the l<eyboard 36 comprises appropriately referenced alphanumeric keysand control keys for the operator to use in entering dialing and dialer control instructions into the automatic dialer 31. The display 92, on the other hand, has numerical indicia and suitable word legends which are selectively illuminated tokeep the operator abreast of the status and performance of the automatic dialer 31.
Provision is made for selectively operating the automatic dialer 31 in an automatic mode or a manual mode to execute dialing instructions entered via the input scanner 33 or the keyboard 36, respectively. When an outgoing call is to be placed without scanning an address card, the operator manually prepares the transceiver 38 to participate in facsimile comrnunications with a remote terminal and then removes the handset 35 from the hook switch 34 to signal the automatic dialer 31 that ~he manual mode has been selected. After confirming that initial diai tone is being rec:eived at the handset 35, the operator serially depresses appropriate ones of the alphanumeric keys on the keyboard 36 while continuing toI isten for and, if necessary, pausing to receive any intermediate ciial tones associated with the telephone number of the remote terminal, much in the same manner as is done when placing an ordinary telephone call. The automatic dialer 31 executes the keyboard entered dialing instructions in real time. Finaily, when the call is answered, the operator listens for a ready tone from the remote terminaland then replaces the handset 35 on the hook switch 34 to inltiate the facsimi!ecommunications. If an error is made in entering the dialing instructions or if the remote terminal fails to answer the telephone call or fails to provide a ready tone, a clear key is depressed to clear the dialing instructions which have been entered, thereby preparing the dialer 31 for another try at placing that same call or a different call.
All other dialing, terminal control and dialer control instructions are -- entered into and executed by the automatic dialer 31 while the handset 35 is in ..

D~Lq~ 382~

place on the hook switch 34 ~o signal that an automatic mode of operation is called for. An immediate or manual start instruction is entered if the operator depresses a stalt key. Alternatively, the operator may choose to enter a delayed start instruction. In ~hat event, the operator depresses the time set key and then enters S a selected time of day for the delayed start by sequentially depressing appropriate ones of the alphanumeric keys followed by either the ~M or PM key. Additionally,the operator may cause the contents of a recal I memory, which is described hereinbelow, to be read oul byte-by-byte on the display 92 by repeatedly depressing a recall key at a rate in excess of a predetermined memory recycling rate.
Iû Moreover, if the recall key and an erase key are repeatedly and alternately depressed at a rate sufficient to prevent recycling, the recall memory is cleared during the read out process. Also, there is a test key which the operator may operate to obtain a read out on the display 92 of the dialing and terminal control instructions read off an address card by the input scanner 33, without having those instructions executed by the automatic dialer 31.
Shared function keys may be utilized on the keyboard 91, provided that provision is made for discriminating between the different instructions which may be furnished by depressing such a key. For example, in the illustrated embodiment, the alphanumeric "û" instruction and the dialer control "erase" ins~ruction are suitably associated with a single key because the automatic dialer 31 requires that the "erase" instruction be immediately preceded by a "recall" instruction, thereby providing a basis for discriminating between the two different instructions associated with that one key.
The display 92 suitably comprises a gas discharge display panel having several spaced apart numerical display elements and legend display elements. In keeping with accepted practices, each of the numerical display elements has a solid anode and a seamented cathode - viz., the cathode is composed of seven electrically isolated segments which are arranged so that any numeral (û-9~ or adash (-) may be displayed by selectively energizing appropriate ones of those 3û xcathode segments. ~he anodes of the severql numerical display elements .

~38Z3 are electrically isolated from one another, but the positionally corresponding cathode segments are electrically interconnected. Similarly, each of the numerical display elements includes an electrically isolated anode and q segmented cathode.
However, each of those segments is sculptured to d~fine an individual letter or symbol of a word legend such as "send", "receive", "test", "recall" or "pause" or of a symbolic legend, such as "AM", "PM" or ":". External electrical connections are made between the cathode segments of each individual legend display element, andinternal electrical connections are made between the cathode segments of different legend display elements.
Under quiescent conditions, the display 92 provides a running time-of-day indication. If a delayed start instruction is entered into the automatic dialer 31, the display 92 additionally displays the time-of-day which has been selected for the delayed start. Hence, the operator can determine at a glance whether there is a delayed start to be executed and, if so, the amount of time remaining until the delayed start is to be carried out. A recall indication is displayed, without blanking the actual or delayed start time-of-day indication, if the subsequently described recall memory contains instructions which have not been executed for one reason or another. Indeed, if the recall memory is nearly or completely full, a flashing recall indication is displayed to warn the operator that the automatic dialer 31 is in 2~ a soft stop state.
To limit the number of display elements re~iuired of the display 92, the actual and delqyed start time-of-day indications are blanked whenever the automatic dialer 31 receives an instruction to exFcute a manual or a delayed start instruction, a test insfruction or a recall instruction and whenever the automatic dialer 31 is switched into a manual mode of operation. When a manual start, a delayed start or a test instruction is being executed7 the dispiay 92 dispiays the dialing and terminal control instructions which are being read into the automatic dialer 31 by the input scanner 33. Similarly, when a recall instruction is beingexecuted, the display 92 displays the data read out of the recall memory. Lastly, when the automatic dialer 31 is being operated in a manual mode~ the display 92 3~23 displays the dialinc3 instructions entered via th~ keyboard gl .
3. A r~Lra ____ trolled E~bodiment Referriny to FIG. 7, a practical and economical embocliment of the automatic dialer 31 takes advantage of the simplicity and flexibility associated with the use oE a programmed system controller 101. For example, relatively straightforward manually set controls 102 may be included to allow the operator to select (a~ pulse or (.b~ dual tone, multiple frequency (DTMF) (c) blind or (d) dial tone respon-sive dialing. An automatic retry capability may be included in the system controller 101 so that calls that are not com-pleted ara automatically retried for a pradetermined number of t.imes, and the operator may use another of the manually set control 102 to cause the retrys to be performed after a long or short pause. Additionally, the automatic dialer.31 :
can readily respond to the indication provided by the hook switch 34 (FIG. 1) to accommodate a manuàl or an automatic mode of operatlon. In short, these and other ~eatures of this invention are more readily implemented in software than in hardware ~ .
The system architecture-depicted in FIG. 7 will be .
better understood upon referring to the spec.ific embodiment of the automatic dialer 31 which is illustrated by FIGS. 9 -16 when assembled as shown in FIG~ 8.
Turning to FIGS. g - 16, it will be seen that the system controller 101 is a PPS-4 microcomputer which is manufac-tured and sold by Rockwell International Corporation, Microelectric Device Division. That unis is described in detail in "PPS-4 Mi~rocomputer Programming Manua~", Rockwell International Corpora~ion Microelectronic Device Division, 8~3 Document No. 29400 N31, October, 1974.
In keeping with a standard configuration ~or thePPS-4 microcomputer, the system cont.roller lOl is a four blt parallel processor having a central processing unit (CPU~ ].02 comprising a twel~e bit address bus 103, an eight bit in~truction/data bus 104 and a single bit multiplexed control bus lOS. A read only ., - 17a -.' -- .

, ~3823 program memory (ROM) 106 and a random access data memor~ (RAM) 107 selectively interact with the instruction/data bus 104 in response to address words which are applied to the qddress bus 103 by q program address register 108 and adata address register 109, respectively. Specifically, when the ROM 106 is addressed by the prograrn address register 108, program instructions are fetchedFrom a predetermined location in the ROM 106 and fed through the instruction/data bus 104 for applicution to an instruction decode register 111, a plurality of general purpose input/output (I/O) devices 112-114, and a keyboard/display (K/D) interface 115. Conversely, when the RAM 107 is addressed by the data address register 109,data is communicated between the RAM 107 and a four bit accumulator 116 via the instruction/data bus 104. If a write or load instruction is being executed, bits 5-8 of the instruction/data bus 104 are used to transfer the contents of the accumulator 116 into the addressed location of the RAM 107. If, on the other hand, a read or fetch instruction is being executed, bits 1-4 of the instruction/data bus 104 are used to transfer data from the addressed location of the RAM 107 into the accumulator 116.
A clock 117 generates A clock pulses at a bqse frequency of, say 199 KHz., and B clock pulse at twice that frequency or 398 KHz. Those clocl~ pulses are applied to the RAM 107, the input/output devices 112-114, and the keyboard/display interface 115, thereby estqblishing a four phase timing cycle for the controller 101. The buses 103-lû5 are cleared Gr reset to a low ("0") logic level and the CPU 102 is prepared to execute any pending instructions during the firstand third phases of each cycle. During the second phqse of each timing cycle, the address inputs of the RAM lû7 are inhibited so thqt the address bus lû3 is available for feeding an address word from the progr~m address register 108 to the ROM 106, thereby identifying the next instruction which is to be given.
If the preceding instruction from the ROM 106 was a data write or read instruction, the instruction/data bus 104 is employed during the second phase of the timing cycle for transferring the data between the RAM 107 and the accumulator 3û 116. At the same time, the instruction decoder 111 sets a W l/O control bit on the .

.

3~23 control bus lû5 to q high ("1") or a low ("0") logic level to signal the RAM 107whether a d~t~ write or read instruction is to be performed. When a data read instruction is pending, the location of the data which is to be transferred from the RAM 107 to the accurnulator 116 is pre-identified by virture of an address word which was applied to ~he RAM lû7 by the data address register lû9 during the fourth phase o~ i-he preceding cycle. Therefore, that instruction is executed during the second phase of the existing cycle. However, a data write instruction is notexecuted until the fourth phase of the existing timing cycle is reached. At thattime, the data address register 109 feeds an address word through the address bus lû 103 to the RAM 107, thereby identifying a desired storage location for the data - - transferred from the accumulator 116 to the RAM 107.
The next instruction i~ read out of the ROM 106 through the instruction/data bus I û~ during the fourth phase of each timing cycle. That instruction is immediately examined by the instruction decode register 111 , whereby the W l/O control bit on the control bus 105 is set to a hiyh ("1") or a low ("0") logic level during the fourth phase of the timing cycle depending on whether the new instruction is an input/output instruction or a data memory (i.e., read or write) instruction. If another data memory instruction is being given, the above-described process is repeated. If, on the other hand, an input/output instruction is being given, the process is modified to provide for a direct transfer of data between the accumulator 116 and an appropriate one of the input/output devices 112-114 or the keyboard/display interface.
Input/output instructions are each composed of two bytes. The first byte is fed from the ROM 106 to the instruction decode register 111 during the fourth phase of one timing cycle, whereby the W l/O control bit on the control bus 105 is then set to a high ("1") logic ievel. That enables the input/output devices 112-114 and the keyboard/display interface 115 and also inhibits the RAM 107 from feeding data onto or accepting data from the instruction/data bus 104 during thenext timing cycle. When the second phase of that next cycle is reached, the program address register lû8 feeds the address word identifying the location of the ;73~ 3 second byte of 1he input/output instruction to the ROM 106 over the address bus 103. That byte is, in turn, read out of the ROM 106 during the fourth phase of that same cycle cnd is then applied to the input/output devicesl 12-114 and the keyboard/display interface 115 via the instructiontdata bus lû4. Bits S-8 of theS second byte of ~he input/outpu~ instruction point to q specific one of the devices 112-115, while bits 1-4 identify the operation which is to be performed by that device.
The program address register lû8 is a twleve bit register which is organized into two sections. The six most significant bits within the register 108 provide a fixed count which can be chqnged only under program control, while thesix least significant bits define a running count which is automatically incremented by one for each tirning cycle of the controller 101, unless otherwise directed under program control. To accommodate branch routines and subroutines, a twelve bit program return register 121 and a twelve bit save register 122 are connected in series with the program address register 108 to provide a two level stack for holding program reentry addresses. For obtaining additional stacking of reentry addresses in the RAM 107, the program return register 121 is split into three segments of four bits each which can be sequentially shifted into and out of theaccumulator 116 under program control. Moreover, the bits being transferred from2Q the program return register 1~1 to the accumulator 116 may be operated on by an arithmetic logic unit (ALU) 123 if an appropriate program instruction is given.
Similarly, the data address register 109 is a twelve bit register which is - divided into three separate four bit segmentsO Usually, the count stored within the register lû9 is incremented or decremented by one under program control for eachtiming cycle of the controller 101. However, the four most and least significantbits of that count may be directly modified under program control by the accumulator 116, and the other or middle four bits may be indirectly modified under program control by the accumulator 116 through an exchange register 124.
The exchange register 124 is a temporary four bit static storage register which may be used to temporarily store the contents of the accumulator 116 or to transfer the ~38Z;~

contents of the accumulator 116 into the middle four bit positions of the data address register lû9.
As will be appreciated, the accumulator 116 is the primary storage for the CPU lû2. It participa~es in the exchange and transfer of all active input and output clata, whe~her received from or enroute to the RAM lû7, the data address register 109, any one of ~he input/output devices 112-114, the keyboard/display interface 115, the prograrn return register 121, the arithmetic logic unit 123, or the exFhqnge reyister 124. Data may be read into or out of the accumulator 1 16, under program control, via bits 1-4 and 5-8, respectively, of the instruction/data bus lû4 lû during the second phase of any timing cycle of the controller 101. Furthermore, data may be transferred to or from the accumulator 116 internally of the CPU 102during other pllases of the timing cycle since those transfers are carried out without using the instruction/data bus 10~. For example, if an instruction commanding a modification of the contents of the program address register lû8 is15 ` given, the flow of data from the accumulator 116 to the program return register 121 and from there to the program address register 108 is completely isolated from the instruction/data bus lû4.
The accumolator 116, the arithmetic logic unit 123, and a one bit carry register ! 25 provide a four bit paral lel adder having carry-in and carry-out 2û capabilities, whereby data words which are rnultiples of four bits may be accommodated.
Additionally, there are a pair of flip-flops 126 and 127 which may be independently set, reset and tested under program control in response to signalssupplied by the instruction decode register I I 1. That means that the flip-flops 126 and 127 may function as status indicators. Here, for example, the flip-flops 126and 127 are set as a section of the RAM 107 which is dedicated to a recall memory approaches and reactes, respectively, a fully loaded state, whereby the recall indication on the display 92 is flashed as the last few recall memory storage locations are being filled and then the automatic dialer 31 is brought to a soft stop 3û if the last of those locations is filled.

;93~3~3 The input/output devices 112-114 for this embodiment qre the standard general-purpose input/output devices qvqilqble from Rockwell Internationql Microelectronic Device Division (under Part No. 10696) for use with the PPS-4 microcomputer. Such of them includes static twelve bit input sampling gqtes, ~ogether with q twelve bit output buffer which cqn be modlfied under program control .
As illustrated, to carry out the present invention, provision is made in the automatic dialer 31 to provide the following input control signals for a Xerox Telecopier transceiver under program controi:
Significance of True or High ("I") Loaic Level State SCANS A forced indication that the trail edge switch (not shown) in ADF 41 is actuated.
TRAYS A forced indication that at least one document remains in tray 43 of ADF 41.
ENADF A document is to be fed by the ADF 41.
FSTSPN The ADF 41 is to feed the document at a fqst feed rate.
SENDL A "send" Iqmp ~not shown) on the scqnner/printer 33 is to be lit.
ONLINL An "on-line" l~mp (not shown) on the scanner/printer 33 is to be lit.
TESTML A "test" iamp (not shown) on the scqnner/printer 33 is to be lit~
RECVL ~ "receiYe" lamp (not shown) on the scqnner/printer 33 is to be lit~
ASPSWN Document transmission rate for scanner/printer 33 to be selected independently of automqtic dialer 31.
TESTBN Test mode command not given to scunner/printer 33.
EOTAL Sound qn audible end-of-transmission alqrm (not shown) within the scqnner/printer 33.
DMTRN Enable main drive motor (not shown) of scqnner/printer 33.
ADSP2N Automatic dialer 31 not to esfablish ~ two, three, ADSP3N ~our or six minute, respectively, document trqnsmission ADSP4N rqte for the scqnner/printer 33.

3~ 3 AD13h~DN Enable billing meter (not shown) within the sc~nner/
printer 33.
DDISSN Scanner/printer 33 enabled to detect a disconnect by the DAA.
DISCTN Scanner/printer 33 inhibited from initiating a disconnect by the DAA.
STRBN Start command not given to scanner/printer 33.
As indic~ted by the legends appearing in FIG. 13~ direct counter parts to most of the above-identified signals are fed from the buffered outputs of the input/output devices 1 12 ~nd 113 to control inputs of the transceiver 38 by means of a suitable lû input interfqce 131, which is included to transform logic levels and to perform simple logical functions. A notable exception exists in the case of ADSP2N, ADSP3N, ADSP4N and ADSP6N~ which qre generated by a decoder 132 in response to the iogic levels of automatic dialer speèd select signals ASPSAN, ASPSBN qnd ASPSPN provided under program control. ASPSAN and ASPSBN allow for four different bit combinations (00, 01, 10 and 11) ~nd, therefore, qre sufficient toindicate whether the scanner/printer 33 is to operate at q document trqnsmissionrate of two, three, four or six minutes/page. ASPSPN is included to provide ~he additional bit that is necessary to signal whether the document transmission rate of the scqnner/printer 33 is to be remotely determined or not.
2û The output signqls of the Xerox 2ûû Telecopier transceiver, which are sqmpled under program control by the ~utomatic dialer 31, are:
Significance of True or High ("I") Signal Loaic Level State SCANS The tri~l edge switch (not shown) in the ADF 41 is qctuated.
TRAYS At least one document remains in the input trqy 43 of the ADFo ENBM The billing meter (not shown) within the scanner/printer 33 is enabled.
XVID The transmitted video represents a bl~ck picture element (white picture elements are represented by a low ("û") logic !evel signal).

.

ELCLK A clock signal generated internally of the scanner/printer 33.
LSYNC A scan line-by-scan line synchronizing signal generated internqlly of the scanner/printer 33.
TESTM Scqnner/printer 33 in a test mode.
AUTOP Scanner/printer 33 in a print mode.
GSTRB A g(ited start button indication from the scanner/printer 33.
DA-TC Data available from the scanner/printer 33.
FIG. 14 shows that direct counter parts of each of these signals are fed through an appropriate output interface 133 to respective ones of the gated inputs of the 1 0 input/output device 11 2.
To enable the automatic dialer 31 to initiate a start by the transceiver 38 under program control, one of the buffered outputs of the input/output device1 12 is used to apply a start signal ASTBP (automatic dialer start button push) to the transceiver 38. The start signal ASTBP is set to a hiyh ("I") logic level under program control only when the automatic dialer 31 is executing a manual or delayed start instruction.
Turning to FIG. 12, the CBS 1001 F data access arrangement 39 employed in the illustrated embodiment completes a voice/data path DR-DAA to a communications link when supplied with control signals irldicating that data ~ is available DA-DAA and that an off-hook instruction O~i-DAA has been given. A
ring detect signal Rl-DAA and a switch hook signol SH-DAA are generated internally of the DAA 39 when a ringing voltage is applied and when the voice/data path DR-DQA is compiete, respectively.
In keeping with this invention, provision is made for generating the DA-DAA and OH-DAA input control signals for the DAA 39 under program control.
Furthermore, the status of the DAA 39 is monitored under program control. In this instance, there is an interface 134~ between the DAA 39 and the automatic dialer 31 which performs several important logical functions in addition to the necessary logic level transformations.
As shown, the input signals applied to the DAA interface 134 are:

38~3 1. The ring detect Rl-DAA and switch hook detect SH-DAA signals supplied by the DAA 39;
2. Automatic dialer switch hook (ASH) and an off-hook inhibit (OHINH) signals which are supplied by the input/output device 113 under progrqm control - ~he ASH signal indicates that the handset 35 of the automatic dialer 31 is off hook and OHINH
signal is an instruction to inhibit the DAA 39 from going off hook under the control of the automatic dialer 31;
3. Autornatic dialer off-hook (AOH), ready (ADA) and ring enable ~RIENBL) signals which are received from a discrete output buffer register 135 (FIG. I l) which, in turn, is loaded by the accumulator l 16 under program control - the AOH, ADA and RIENBL signals indicate whether the automatic dialer 31 is on-line, ready and prepared for an incoming call, respectively; and

4. A 777 Hz signal gated at a 24 Hz rate which is provided by an AND gate 136 (FIG. 14~ in response to 777 Hz and 24 ~Iz input signals supplied by a multistage frequency divider 137 which, in turn, is supplies with q TTL compatible input signal at the A
clock rqte of 199 Hz by the input/output de~ice 112.
The functions the DAA interface 134 performs in response fo these input signals include: n 1. Supplying the DAA 39 with a DA-DAA control signal whenever the autonnatic dialer is in a ready state as indicated by the ADA signal Gnd with an OH-DAA control signal whenever the - 25 automatic dialer is on line as indicated by the AOH unless the automatic dialer is requesting that the DAA 39 be inhibited from going off hook as indicated by the OHINH signal;
2. Feeding to the gated inputs of the input/output device 113, the DA-DAA and OH-DAA control signals being fed to the DAA
39, a ring feedback signal RIFB when a ring detect signal Rl-.~

3l~323 DAA is present, a signql Rl-TC indic~ting that there is an incoming call for the transceiver 38 to answer when à ring detect signal Rl-DAA and a ring enable signal RIENBL are present, a signal SH-TC indicqting that the transceiver 38 is off hook or busy when a switcll hook signal is being received From either the DAA 39 (SH-DAA) or the automatic dialer 31 (ASH), and a gated ring feedback signal RISKFB when a ring detect signal Rl-DAA, a ring enable signal RIENBL and the gated 777 Hz signal are present; and 3. Applying to a discrete input buffer 137 (FIG. I l) a switch hook feedback signal ASFB in the absence of a DAA switch hook signal SH-DAA.
Here the gated ring feedback signql RISKFB is also used to drive an audible aiarm 138, whereby the operator is advised that the transceiver 33 is about to answer an 15incoming cqll.
To bring this discussion into sharper focus, reference is additionally made to FIGS. 17 and 18 for a review of the operation of the automatic dialer 3i.
When power is first applied, the program address register 108 (FIG. I l) is reset or cleared, thereby automctically returning to the starting address for a routine which initializes the automatic dialer 31 and the transceiver 38 as indicated at 2û 1. Next an idle loop routine is performed until a condition requirina an entry into one of three branch routines is detected. Sequential sampling is carried out while the idle loop routine is being performed to determine whether there is a ringing voitage applied to the DAA 39 (FIG. 12~ as indicated at 202, whether the dialer handset 35 (FIG. I) is off hook, as indicated at 203, and whether an autostart command has been given as indicGted at 204. The branch routines performed when one or the other of these conditions is detected are dedicated to allowing the transceiver 38 to Gccept incoming calis, the manual mode of operation of the automatic dialer 31, and the automatic mode of operation of the automatic dialer 31, respectively.
More particularly, if the automatic dialer 31 detects a high ("1") logic ,.

level ring feedback RIFB signal at the input/output device 11 3 (FIG. 1 2) whileperforming the idle loop routineJ the program address register lû8 causes the ROM
106 to alternately enter into and exit frorn an incoming call branch routine until a high ("I") 109ic level off-hook feedback signal OHFB is detected at the discreteinput buffer 137 (FIG. I l) to confirrn that the ~rarlsceiver 38 has answered the incoming call as indicated at 2û5. In this instance, as shown in FIGS. 13 and 14, the off-hook feedback signal OHFB is fed into the input buffer 137 by the transceiver output interface 133 in response to an off-hook signal which is generated internally of the transceiver 38 when it is on line. After confirming that the transceiver 38is lû on line, the ROM lû6 continues with the branch routine to allow the automatic dialer 31 to determine whether an address card is being scanned or not as indicated at 2û6 and, if not, whether the disconnect has been performed or not as indicated at 2û7.
To detect the scanning of an address card~ the BSVID video signal I S applied to the input/output device 11 2 (FIG. 13) is more or iess continuously compared against a picture element sequence stored in the RAM lû7 to represent the predetermined seauence of picture elements which are generated when the distinctive bar code 84 is being scanned. If an affirmative comparison occurs, the signals necessary to disconnect the call are applied to the transceiver 38 and the ~?O~ a, 2û 9 DAA 3~ under program control as indicated~at ~ Otherwise, the call is allowed to continue to normal completion as indicated at 207. In any event, when the call is disconnected, the automatic dialer 31 returns under program control to the idle loop routine.
If a high ("I") logic level hook switch HOOKSW signal is detected at another discrete input bvffer 138 while the idle loop routine is being performed, the automatic dialer 31 exists under program control from the idle loop routine and enters a branch routine dedicated to the mGnual mode of operation of the avtomatic dialer 31. As will be seen upon referring to FIG. 9, the hook switch HOOKSW signal is taken from the set or Q output of a flip-flop 141 which is set and 3û reset in response to the off-hook and on-hook status, respectively, of the dialer ~ L~3~ 3 hook switch 34.
Upon entering the manual operqting mode branch routine, instructions are given under prograrn control to read and store the digits the operator enters via the l<eyboard 36 and then dial out, as indicated at 2û8. Thus, a review of how these functions are perFormecl is in order.
As shown in FIGS. I l and 15, the keyboard/display interface 115 for this embodiment is the general-purpose keyboard/display device provided tunder Pqrt Nc. 10788) by Rockwell International Microelectronic Device [)ivision for use with the PPS-~ microcomputer. Thus, the keys of the keyboard 36 are assembled in rowslû and columns to be read column-by-coiumn and row-by-row via bits 5-8 of the instruction/data bus 104 when a keyboard-read instruction is given. In more detail, when such an instruction is given, the column leads Xo-X4 are sequentially strobed during successive timing cycles while the row leads Yo-Y3 are read into the accumulator 116 on bits 5-8 of the instruction/data bus 104 for subsequent transfer to the exchange register 124. If a key within the column being strobed has been depressed, that bit will be at a high ("I") logic level, rather than a low t"0") logic level, it being understood that the leads YU-Y3 are normally held at a low ("0")logic level by virtue of being returned to a suitable low logic level supply source (-SVDC) through respective voltage dropping resistors 141-144. The contents of theexchange register 124 are, in turn, used to cquse the program address register 109 to generate an address for reading a predetermined four bit representation of the depressed key into the accumulator 116 for subsequent transfer back to an activedata storage address within the RAM 108. The process is repeated as further keysare depressed.
The binary representations (û-9) for the digit keys which are operated are read in order into successive addresses of a segment of the active data storage section of the RAM lû8 which is dedicated to characterizing the numerical indicia which are to be displayed. Another segment of the active data storage section ofthe RAM lû8 is dedicated to identifying the legends which are to be displayed.
3û To display the appropriate digital indicia and/or legends on the display 92, there are separate addresses within the display dedicated active data storage .

3~23 section of the RAM iO8 for each of the numerical and legend display elements of the display 92. Those addresses are blanked, unless data is entered to indicate that the associated display element is to be illuminated. Numerical indicia to be displayed are each characterized by four bits, thereby uniquely identifying the specific numeral (û-9). A legend, on the other hand, is adequately characterized by setting a predetermined one of the four bit represen~ation to a high ("I") or low ("û") logic level, depending on whether the legend is to be displayed or not.
If, say, the displayed digits and legends are to be updated, the four bit representations for the numerical and legend display elements are transferred, lû under program control, from the RAM 108 to be accumulator 116 and then via bits 1-4 of the instruction/data bus 104 to the keyboard/display interface 1 15 where the digit representations and the legend representations are shifted into separate storage registers (not shown). The anodes LAU-LA7 and DAU-DA7 of the legend and numerical display elements within the display 92 are sequentially strobed byappropriate drivers 145 and 146, respectively, while successive groups of four bits each are being shifted out of both interface storage registers. Furthermore, a steering bit DBS is applied to a pair of switches 147 and 148 to cause the drivers 145 and 146 to selectively strobe the anodes of the display elements on the lefthand side or the right-hand side of the display 92, depending on whether bits are being 2û shifted out of the upper halves or the lower halves of the interface storage registers. A decoder 149 sequentially decodes the four bit representations DAI-DA4 of any numerical indicia which are to be displayed, thereby energizing appropria~,e ones of the cathode segments of the numerical display elements in timed synchronism with the strobing of the anodes of the different elements by which successive ones of tliose indicia are to be displayed. As previously mentioned, one bit VBI is sufficient to indicate whether a legend is to be displayed or not. Thus, a switch 151 is operated in response to that one bit DBI of each of the four bit iegend representations to se!ectively energize the cathodes of the legend display elements in timed synchronism with the strobing of the anode of any legend display element which is to be illuminated. Of course, legends and numerics iLa3 313~ 3 may be displayed jointly or independently under program contral.
Dialing is accomplished by pulsing the autodialer off-hook signal AOH
(FIGS. I l and 15) or by generating suitable dual tone, multiple frequency (DTMF) dialing signals through the use of a tone generator 153 (FIG. 10). A switch 102a(FIG. I l) is set by the operator to input a high ("I") or low ("û") logic level signal ~o the discrete input buffer 138, thereby indicating whether DTMF or pulse-type dialing is to be employed. In either event, the digits to be dialed are represented by the four bit numerical representations stored in the active data, display dedicated segment of the RAM 108 when there is a call to be placed so that thosedigits are more or less concurrently displayed and dialed.
- If pulse-type dialing is selected, the four bit representations of the digits to be dialed are sequentially transferred, under program control, from the active data section of the RAM 108 to a dial counter address within the RAM 108.In the course of that process, any "0" digit is converted to a four bit representation of "Ib". Each digit is dialed out before the next digit is read into the dial counter.
To thàt end, the automatic dialer available ADA signal is held at a low ("0") logic level while the automatic dialer off-hook AOH signal provided by the discrete output buffer 135 (FIG. I l) is alternately switched bet~een a high ("I") and a low ("0") logic level, under program control, at a frequency and with a repetition rate selected to cause the DAA off-hook OH-DAA control signal (FIG. 1~) to emulate a dialing pulse. As each dialing pulse is generated, the value of the digit being dialed is decremented by one, until the value reaches zero to confirm that the dialing of the digit has been completed. After a suitable delay~ the process is repeated. As successive digits are transferred into the dial counter section of the RAM lû8~ a count stored within a dial location address of the RAM 108 is incremented by one, under program control5 so that the last possible digit to be dialed out is marked by the dial location counter reaching a predetermined vqlue, thereby allowing for atimely termination of the dial out routine.
For DTMF dialing, the four bit representations of the digits to be dialed are sequentially transferred to the TTROWI-TTROW4 and TTCOLI-TTCOL4 inputs -- 3û --38f~'3 of the ~one generator 153 (FIG. 10) under program control. Two input/output instructions ar~ utili~ed per digit, whereby the four bit representation of each digit is fed through the input/output device 114 to the TTROWI-TTROWI inputs of the tone generator 153 in response to one instruction and to the TTCOLI-TTCOL4

5 inputs in response ~o another instruction. The ~one generated by the tone generator 153 is fed through a normally open contact 154 of a relay 155 (FIG. 9) to the voice/data path DR-DAA provided by the D~\A 39 (FIG. 12) which, in turn, appliesit to the communications link. Again, the dial location counter provided by the RAM 108 is used to signal the completion of the dial out routine, and a suitablelû interval of time is maintqined between the dialing of successive digits to avoid confusion. The tone generator 153 is, however, isolated from the transceiver 38 to avoid applying false data or control signqls to the transceiver 38. To that end, the data path DR-TC for the transceiver 38 is coupled to the data path DR-DAA of theDAA 39 through a normally closed contact 156 of the relay 155.
Returning now to FIG. 17 to complete the description of the manual mode branch routine, it will be seen that the ROM lû6 recycles to the dial out instruction 2û8 until the dialer hook switch HOOKSW signal at the input buffer 138 drops to a low ("û") logic level, thereby indicating that the dialer handset 35 is in place on its hook switch 34 as indicated at 209. A high ("û") logic level ARELAYN
is then fed from the input/output device 113 (FIG. 12) to the coil 157 of the re!ay 155 (FIG. 10) to ensure that the data path DR-TC of the transceiver 38 is cut through to the voice/data path DR-DAA of the DAA 399 and a predetermined time out period starts to run. Specificqlly9 a high ("1") logic level off-hook feedback OHFB signal must be detected at the discrete input buffer 137 before a high ("1") logic level TIMEOUT signal is detected at the other discrete input buffer 1 3B (FIG.
I l). Otherwise, the ROM 106 will return to idle loop routine due to a failure oF the transceiver 38 to start, as indicated at 211. If the transceiver 38 does start, the communication continues to a norma! disconnect, as indicated at 207, unless a forced disconnect 208 is called for as a result of the transceiver 38 starting to scan an address card, as indicated at 206. Of course, when a normal or forced 1~38;~

disconnect occurs, the ROM 106 returns to the idle loop routine.
As shown in FIGS. 10 and ! 1, programmed delay timing is performed by a programmable counter 161 which sets a flip-flop or latch 162 when a time out occurs, thereby causing the TIMEOUT signal provided by the latch 162 to go to a high ("1") logic level. When delay timing is called for, the counter 161 and thelatch 162 are reset or cleared, under program control, in response to a reset signal TIMEOUT supplied by the input/autput device 113 (FIG. 12). Further input/output instructions are then given to cause a single or multiple place binary count to be loaded into the coun ~er 161 via outputs TBCD I -TBCD4 from the input/output lû device 114. That count is then decremented toward zero in response to clock pulses supplied by freauency divider 137, whereby a time out is signalled when the count reaches zero. Here, the basic frequency fo the decrementing clock pulses is approximately 3.1 KHz. However, there is a divide-by-eight stqge (not shown) in the clock input of the counter 161 which is selectively bypassed if a control bit 8-BYPS supplied by the input/output device 113 is set, under program control, to ahigh ("I") logic level. Therefore, if the counter 161 has, say, the capacity to store a sixteen place binary count, any time out period from 320 microseconds to 216 x320 microseconds x 8 (to account for the divide-by-eight stage) - viz., 45 minutes -may be programmed into the counter 161.
Turnina again to FIGS. 17 and 18, if an automatic start command is received, as indicated at 204, while the idle loop routine is being performed, the ROM JQ6 branches into an au~tomatic dialing routine. A "START" button on the - keyboard 36 may be depressed to generate an automatic start command or the actual or running time-of-day kept by an AM-PM clock 163 (FiG. 10) may come intocoincidence with a delayed start time-of-day previously read into the RAM lû8 through the use of the keyboard 36. For that reason, the keyboard 36 and the AM-PM clock 163 are periodically read while the idle loop routine is being performed, and the running time-of-day indication provided by the clock 163 is periodicallycompared against any delayed start time-of-day stored in the RAM 108. Any "START" button command Gnd any delayed start timeofday are read into the RAM

3~3 108 by the previously described keyboard reading process. Therefore, there is noreason to repeat that description. Instead, it suffices to note that the entry of a time-of-day for a delay start is initiated by depressing the "TIME SET" key on the keyboard 36. Thereafter, an appropria~e one of the "AM" or "PM" keys is depressed, and ~hen ~he digi~ l<eys are operated to identify the AM or PM hour and minute for the delayed start, starting with the digi~ for the most significant unit of time and proceeding in turn to the digit for the least significant unit of time. The four bit representations for the "AM" or '7PM" key qnd the time identifying digit keys are stored in predetermined addresses within the active datq storage section of the RAM 108 for display on the right-hand side of the display 96 and for comparison against the actual time-of-day kept by the AM-PM clock 163. Those bits are, however, transferred into a temporary storage section of the RAM lû&
whenever the ROM lû6 branches into the manual mode routine, a test routine (not shown) or a recall routine, or if an automatic start command is given.
As shown in FIG. 10, the AM-PM clock 163 for this embodiment is a twelve hour clock which is driven by the ordinary 60 Hz line frequency. A normally open switch lû2b is included so that the operator may set the clock 163 to the correct time by selectively applying a reference level voltage (say, ground) to a FASSET input for coarse adjustments or to a SLOSET input for fine adjustments.
Suitably, the AM or PM sianificance of the running time-of-day is indiated by alternately setting and resetting the flip-fiop 126 (FIG. 1~ as the running time of-day rolls over from the last minute ot the twelfth hour to the first minute of the first hour.
A self-contained strobe within the clock !63 provides a four bit strobe pattern on strobe leads HR10, HRI, MIN10 and MINI to identify the particular unit or place position of the running time-of-day which is currently represented by the four bit binary representation on digit leads CE3CDI-CBCD8 are read to obtain a four bit representation of the current value for that particular place position. The process is repeated~ place position-by-place position, to obtain a full characterization of the existing time-of-day. The four bit representations of the .

38~:3 existing values for ~hose place positions are read into the active storage section of the RAM 108 for display on the left-hand side of the display 96, but qre subject to being displaced therefrom if the ROM lû6 branches into the manual mode routine, a test routine or a recall routine, or if an automatic start cornmand is given.
If a delayed star~ tirne is loclded into the RAM lû8, the actual time-of-day and the time-of-day selected for the delayed start are periodically comparedunder prograrn control, to detect coincidence. To that end, the AM-PM indications, the more significant place values, and then the less significant place values for the actual and delayed start times are compared in order, until a lack of coincidence is 1 0 found.
Returning to FIGS. 17 a~d 18, if the actual time-of-day coincides with the time-of-day selected for a delayed start, or if an immediate start command is entered by operating the "START" key, the ROM lû6 branches into an automatic start routine under program control to determine whether the start command is tobe executed or not as indicated at 212 If a dedicated recall rnemory section of the RAM 10?3 is full as indicated by, say, the flip-flop 127 being in a set state, if the transceiver 38 is off-hook as indicated by a high ("1") logic level off-hook OHFB
signal at the input buffer 137, or if the input tray 42 of the automatic document feeder 41 (FIG. 2) is empty as indicated by a low ("0") logic level BTRAY signal at the input/output device 113, the ROM lû6 exits from the automatic start routine and returns to the idle loop routine. Otherwise9 the ROM J 06 provides an instruction 213 which causes the transceiver 38 to feed and start to scqn the first or bottommost document in the input tray 42 of the ADF 41 (FIG. 2). The BYSYNC
signal applied to the input/output device 11 3 is monitored for a positive-to-negative transition which marks the completion of the first scanning cycle, and then the count representing a predetermined time out period is loaded under program control into the programmable counter 161 as previously described.
If the counter 161 times out before the distinctive bar code ~34 (FIG. 5~
along the borders of an address card is detected, the ROM 106 provides, as indicated 214, an instruction 215 which causes the document feeder 41 to eject the 3~ 3 document and directs that appropriate entries be made in recall memory, as indicated at 216. The absence of the bar code 84 indicates that the document wasnot an address card or a pause card. If there is another docùment in the input tray 42 as indicated by a high ("1") logic level BTRAY signal at the input/output device 113, the ROM lû6 returns to the feed and scan instruction 213. If not, the ROM
lû6 returns to the idle loop routine, as indicqted at 217.
If the bar code 84 is detected, another predetermined count is loaded into the counter 161 under program control to provide a fixed time-out period for detecting the bar code 87 marking the first row of the address card instruction field 85. Should a time out occur, the ROM lû6 provides the eject instruction 215 and the recall entry instruction 216 and then looks for another document in the ADF tray 42, as indicated at 217, on the assumption that the address card is misoriented.
When a border bar code 84 and a row bar code 87 are detected on time, the ROM 106 provides instructions 217 to (1) read the mark sense identified terminal and dialing control instruction in the instruction field 85 of the qddress card into the active data section of the RAM 108 for display on the display 96;
provide the transceiver 38 with the appropriate input control signals for executing the terminal control instructions; loàd a preselected count into a predeterminedredial counter address within the RAM 108; and cause the document feeder 41 to eject the address card after the last instruction has been read.
As previously mentioned, the mark sense identified terminal and dialing control instructions are decoded by utilizing the bar code 87 preceding each row of the instruction field 85 as a timing reference. That process yields a four bit representation for each mark sense identified instruction that is scanned, unless two or more mark sense identified instructions are encountered during the scanning of any given row. If that occurs, blanks are loaded into the RAM address for theinstruction from that row under program control. To that end, the flip-flop 126 (FIG. Il) is reset in response to the detection of each bar code 87 and set in response to the detection of each mark sense identified instruction, and blanks are 3i~i3;;~3 loaded into the RAM address for ony given row if a mark sense identified instruction is detected while the flip-flop 126 is in a set state.
Each tirne a row bar code 87 is detected while the flip-flop 126 is in a set state, a predetermined coun~ is loaded into -~he counter 121 to obtain a high ("1") logic level TIMOUT signal at the discrete input buffer 137 whenever two rows or an equivalent segment of the address card is scanned without detecting a marksense identified instruction. That, in turn, causes the Ro~ 106 to issue an instruction for ejecting the address card from the ADF 41 and to initiate a dial-out routine as indicated at 219.
The decoded dialing and terminal control instructions are stored in the active dqta section of the RAM 108 for display on the display 96. Pulse or DTMF
dialing is performed in response to these instructions in the manner described above, except that initial and intermediate dial tones are accommodated by pausing For a predetermined period of time, if blind dialing has been selected, or by waiting until dial tone is detected, if dial tone responsive dialing has been selected. A
switch 102c is manually positioned by the operator to apply a high ("1") qr a low ("O") logic level signal to an input of the discrete input buffer 138 (FIG. I I), thereby reflecting the option which has been selected.
For blind dialing, a predetermined count is ` loaded into the programmable counter 161 (FIG. 10) whenever the four bit representation of an initial or intermediate dial tone is read out of the RAM lû8 during the dial-outroutine. That routine is then suspended for a predetermined amount of time, until a high ("I") logic level TIMOUT signal is received at the input buffer 137 (FIG. I l) to indicate that the time allotted to the acquisition of dial tone has expired.
When dial tone responsive dialing is selected, a predetermined time out period is allotted to the acquisEtion of any initial or intermediate dial tone, but the dial-out routine does not resume until there is a high ("I") logic level busy back/dial tone signal BUSYDT at the input/output device 114 (FIG. Iû) to confirm that diaitone has been received. If a time out occurs before dial tone is received, the ROM
lû6 suitably advances under program control to the redial subroutine described hereinbelow.

As shown in FIG. 9, to perform the busy back/dial tone detection function, this embodiment includes q bandpass filter 17 i, which has a passband roughly equal to the passband of an ordinary voice grade ~elephone channel, for coupling the data/voice path DR-DAA of the DAA 39 (FIG. 12) to a series detectorS circuit cornpri~in~ a ISûO ~1~ notch filter 172, a lirniter 173~ a 300 Hz - 700 Hz bandpass fil~er 174 and a threshold detector 175. Much of the extraneous noise outside the 300 Hz to 700 Hz range normally used for dial tone and busy back signalling is eliminated by thè bandpass filters 171 and 174, but the notch filter 172 provides an additional measure of protection against a false BUSYDT indication by sharply attenuating any energy at the 1500 Hz ~requency used for handshaking purposes. Even with that protection, there may be circumstances where sufficientenergy applied to the threshold detector 175 to cause it to generate a high ("1") logic level BUSYDT signal in the absence of a busy back or dial tone signal, butthat situation is straight forwardly dealt with by validating the BUSYDT signal only if it remains at thst logic level for a suitably long period of time~ Of courseS the limiter 173 protects the bandpass filter 175 and the threshold detector 176 against the potentially damaging effects of excessively high signal levels.
When dialing is completed, the RONl 106 provides instructions 221 which cause the tone generator 153 (FIG. 10) to feed an appropriate handshaking signalthrough the DAA 39 in an attempt to establish communications with the remote terminal being called. Specifically, for the Xerox 200 Telecopier transceiver compatible case, the tone generator 153 is instructed to supply a combinotion of1200 Hz tones or an alternating 18ûO/1500 Hz tone, depending on whether the transceiver 38 is to operate in a transmit mode or a receive mode as determined by the terminal control instructions stored in the RAM 108. During the dialing an initial handshaking, a low ("0") logic level ARELAYN signal is generated under program control so that the tone generator 153 is cut through to the voice/data path DR-DAA of the DAA 39. At the same time, high ("I") logic level AMIC and AEAR signals are provided to open circuit switches 176 and 177 which are 3û connected in series with the transmitter 35a and receiver 35b sections of the handset 35.
Another count is loaded into the counter 161 when dialing is completed to provide the remote terminal with a predetermined amount of time tp respond tothe handsh~king signql supplied by the tone generator 153. During this period, the input/output clevice I 14 (FIG 10) is sampled for a high ("1") logic level busy bacl~/tone detect signal BUSYVT, as indicated at 222, and for a high ("1") logiclevel acknowledgment signal VGRACK, as indicated at 223. Additionally, the inputbuffer 137 (FIG I l) is sampled for a high ("I") logic level time out signal TIMOUT.
If an acknowledgment is detected, the ROM lû6 provides the necessary instructions for cutting the transceiver 38 through to the voice/data path DR-DAA of the DAA
39 and for otherwise preparing it for operation, as indicated at 224-230. If, on the other hand, a busy link condition is detected, the ROM 106 initiates a redial subroutine, as indicated at 241-243. Or, if a time out occurs without detecting a busy back signal or an acknowledgment signal, the ROM 106 aborts the job with anIS appropriate recall entry instruction 216.
In keeping with the customary handshaking protocol of a Xerox 2ûû
Telecopier tronsceiver, the remote terminal is expected to generate an intermittent 1500 Hz acknowledgment or ready signal in response to either of thehandshaking signals which can be provided by the tone generator 153. Thus, to provide for the detection of such an acknowledgment signal, the voice/data path DR-DAA of the DAA 39 is coupled through the bandpass filter 171 to another series detector circuit which, as shown in FIG. 9, comprises a 300 Hz - 700 Hz notch filter 1~31, a protective lirniter 182, a 1500 Hz bandpass fiiter 183, an integrator 184 and a threshold detector 185. Accordingly, a high (" I ") logic level acknowledgmentsignal VGRACK is supplied by the threshold detector 185 only if there is a substantial amoutn of persistent energy at or about the 1500 Hz center frequencyof the bandpass filter 183. Transients are in large part ignored because of the time constant associated with the integrator 184. Additionally7 the threshold detector 185 advantageously includes a voice guard circuit (not shown) to prevent 1500 Hzenergy accompanied by significant amounts of energy at other voice band 3~3~3 frequencies from being misinterpeted as an acknowledgment signal. Nevertheless, the preferred practice is to require that the VGRACK signal remain at the high ("I") logic level for a predetermined period of tirne before being accepted as a valid indication that an acknowledgment has been received.
If c valid high ("I") logic level acl<nowledgment detect signal VGF~ACK
is received before the post-dialing time out period expires, a determinatiori ismade, as indicated at 224, whether the terminal control instructions which were given call for the transceiver 38 to operate in a transmit mode or a receive mode.
If the transceiver 38 is being operated in the receive mode, the off-hook OHFB
signal at the input buffer 137 is repeqteclly sampled, under program control, todetect the disconnect 225 which occurs when the communication is completed. At that point, the ROM 106 is returned to the starting point for the automatic modebranch routine to determine, as indicated at 212, whether another automatic start may be carried out.
In the event that the inquiry 224 leads to the conclusion that the transceiver 38 is being instructed to operate in a transmit mode, the ROM 106 responds by providing an instruction 226 to feed and scan the next document. As the lead edge of that document is being scanned, the BSVID signal appearing at the input/output device 112 (FIG. 14) is sampled to determine, as indicatèd at 227, whether an address card or a pause card is being scanned. If so, the ROM 106 provides a forced disconnect instruction 228 to disconnect the call and to terminate the feed and scan.
Returning for a moment to FIG. SB, it will be seen that a pquse card 88 has a distinctive border bar code 89 ulong the leading and trailing edges of its front and rear sides. The characterizing feature of the pause card bar code 89 is that it contains the address card border bar code 84 in qddition to a distinguishing code segment 9û. Moreover, unlike the address cards 81a-81c (FIG. 5A), the pause card89 is symmetrical and, therefore, does not impose a critical orientation requi rement.
Turning back to FIGS. 17 and 18, when the transceiver 38 is operating in ~3823 its transmit mode, the ROM 106 repeats the feed qnd scan next document instruction 226 as necessary to allow for the transmission of the information content of successive subject copies destined to the same remote terminal. Each of those documents is examined to determine whether a forced disconnect instruction 22~ should be given because ar- address card or a pause card is being scanned. Furthermore, the off-hook feedback OHFB signal is sampled to determine, qs indicated at 229, whether a normal disconnect has occurred.
When a forced disconnect instruction 228 is given, a determination is made, as indicated at 231, whether the scanning of the distinctive border bar code 9û (FIG. 5) of a pause card was responsible for that instruction being given. If so, a predetermined count is loaded into the programmable counter 161, under program control, to suspend the automatic mode of operation of the automatic dialer 31 for a predetermined period of time as indicated at 232. If not, or if a normal (non-program initiated) disconnect was detected, the ROM lû6 immediately returns to IS the starting point of the automatic mode branch routine to determine, as indicated at 212, whether another automatic start is permissible.
As will be recalled, the programmable counter 161 (FIG. 10) for the particular time-out embodiment has the capacity to provide a time-out period of up to 45 minutes. Suitably, the delay 231 allotted to each pause card is selected to equal a predetermined fractional portion of that period, such as one half or, inother words, 22.5 minutes. Ihat provides ample time for the transceiver 38 to accommodate a few incoming calls or for an operator to use the automatic dialer 31 in its manual mode to place a few outgoing calls. Moreover, if additional time is needed, two pause cards may be stacked one after another in the input tray 42 totake advantage Gf the full capacity of the counter 161. It should be noted that when an automatic start command is given, the ROM 106 provides appropria~e instructions (not shown) for initializing the transceiver 38 in its test mode to scan at its two-minute documetn transmission rate, and that the transceiver 38 remains in that mode until contrary instruc~ions are provided as a result of scanning anaddress card with mark sense indicia identifying terminal control instructions or as .. ' ~ ' :

a result of s-tar-ting to scan a document which does not have the distinctive address card border bar code 84.
When the pause card initiated delay period expires, as indicated by the appearance o a high ("1"~ logic level TIMOUT signal at the input bu~fer 137 tFIG. 11~, the BTR~
signal applied to the input/output device 112 is sampled to determine, as lndicated at 217, whether the ADF tray 42 (FIG. 2) is now empty or not. If so, the ROM 106 returns to the starting point 212 for the idle loop routine. If not, the RoM106 provides another feed and scan instruction 213 to re-initiate the automatic mode of the dialer 31.
In passing, it is worth mentioning that each pause card 90 should.be preceded by and ~ollowed by anoth~r pause card or by an address card, as. shown in FIG. 4. A flag 233 is set after an initial correctly marked and oriented address card is scanned to allow the transceiver 38 to scan pause cards, despite the neyative result of the address card correct inquiry 214, as indicated at 234. That inquiry 214 does, however, lead to a job abort with an appropriate recall entry 2G 216, if a pause card is not preceded by and followed by an-other pause card or an address card.
Focusing now on the redial subroutine, i~ will be seen that if a high ("1") logic level busy back/dial tone detect signal BUSYDT is applied to the input/output device 114 (FI5. 10) during the post-dial out time out period, an inquiry 241 is made, under program control, to dete~mined whether the redial count stored in the ~AM 108 is equal to zero. If that count has n~t yet reached zero, the ROM 106 issues a delay instruction 242 and an instruction 243 to decrement the redia-l counter by one before returning to the - dial-out instruction 219 for the purpose of making another .:f. .

38~3 a-ttemp-t a-t placing the call in accordance with the dialing instructions in the active data section of the RAM 108.
I~ a busy link is repeateclly encountered, the redial count ultimately reaches zero. When that occurs, the ROM 10~
exits ~rom th~ reclial subroutine with an instruct.ion 216 to make an appropriate entry into the recall memoxy section of the ROM 108.
~esirably, there is a manually operable switch 102d for applying a high ("1"~ or low t"0") logic level control signal to the discrete input bu~fer 138 so that a lon~ or short redial delay period may be selected by the operator. Tha~ option is easily accommodated by simply altering the caunt that is loaded into the programmable counter 161 when executing the delay instruction 242 to reflect the setting of the switch 102d.
Concentratiny on the recall memory, it will be evide~t at this point that an appropriate recall memory entry inst~uction 216 is given by the ROM 106 whenever there is an operator induced error or a.line fault condition which ~rustra es an attempt to automatically place or complete an outgoing call. Advantageously, the entry made in the recall memory identifies th~ problem which was encountered and the number o~ documents which were affected with suffici nt particularlty to isolate the problem and to provide full accountability for all documents. ~.
5uccessive addresses are reserved in the RAM 107 to serve as the recall. memory. If one or more of those addresses are full, a command to illuminate the "RECALL" legend on the display 92 is loaded into the appropriate address within the active data storage section of the RAM 107. Moreoverg if all or nearly all (say, 80%~ of the recall memory addresses - 42 -- . -, . ~ , ' .

38~3 are full, a soft stop flag is set by, say, setting the flip-f]op 127 (FIG. 11) and the "RECALL" legend command is peri-odically blanked 50 that the "RECALL" legend 1ashes "on"
and "o~" to indicate that a soft stop condition e~ists due S to a ull recall memory.
Moxe particularly, as shown in FIG. 19, the contents o th~ "REC~LL" legend address i9 periodically read out of the RAM 107, as indicated at 261, while the ROM 106 is performing the idle loop routine. When an automatic start command is given, as indicated at 204, the recall memory flag is checked, as indicated at 212a, to determine whether ~he recall memory is full or not. If so, or _ 42a -~3~323 i~ any other flag has been set to inhibit the automatic start, the ROM lû6 exitsfrom the automa-~ic mode branch routine and returns to the idle loop routine.
Otherwise, the ROM 106 gives the feed and scan instruciton 2i3 to initiate the automa~ic start and, if a correctly oriented address card is encountered, appropria~e ones oF ~he instructions 21~, 219 and 221 (FIG. 18) for executing any terminal control and dialing instructions identified by mark sense indicia on the address cardt as indicated at 262.
If the first document scanned when înitiating an automatic start is not a properly oriented address card, the operator has made an error in loading the lû documents into the input tray 42 of the automatic document feeder 46 (FIG. 2~, unless the document should happen to be a pause card and the pause card fiag is set, as indicated at 234 (FIG. 18). In the event of such an error, the nature of the error is identified, as indicàted at 263, and a preselected code representing that particular error is entered into the next available or empty address within the recall memory section of the RAM lû8, as indicated at 264, tagether with a countrepresenting the number of additional documents which are scanned before reaching a subsequent address card or pause card. For example, if the first document scanned when the ROM 106 enteres the automatic mode branch routine is not a properly oriented address card, a "I's" code is suitably loaded into the recall 2û memory in place of a telephone number. Similarly, if the document scanned when the ROM 106 recirculates to execute another automatic start after having attempted to operate the transceiver 38 In a polling mode is not an address card, a "2's" code is typically loaded into the recall memory in place of the telephone number. Further, in the event that the first document scanned after performin~ apause is not another pause card or an address card, a "3's" code might be loadedinto the recall memory. Moreover, if an improperly oriented (upside down or backwards) address c~rd is encountered, a dash ("~I's") code is loaded into the recall memory in place of the telephone number.
Essentially the same procedure is utilized to identify any outgoing calls which could not be completed and successfully concluded in response to the scanning of a properly oriented address card, except that any available and unambiguously identified terminal control and dialing instructions are retained in the recall memory. For example, if the call could not be placed because essential terminal control or dialing instructions were omitted or ambiguously identified, as indica~ed at 265, the unambiyuously identified instructions are entered into -~he n~xt available recall memory location, along with dashes ("-'s") in place of themissing or ambiguously identiFied instructions, as indicated at 266. On the other hand, if the call could not be completed because of a persistent busy link status, as indicated at 267, or was completed but could not be successfully concluded because of a premature disconnect or a failure of the receiving terminal to provide a timely acknowledgement signal, as indicated at 268, the telephone number being called and the operating mode requested of the transceiver 38 is entered into the next available address in the recall memory, as indicated at 271 and 272, respectively.
If the data address register 10g addresses the last recqll memory storage location within the RAM 107 while the above-described recall entries arebeing made, recqll data is entered into that location and then the ROM 106 returns, as indicated as 273, to the idle loop routine. Likewise, if the BTRAY signal applied to the input/output device 112 (FIG. 13) drops to a low ("0") logic level to indicate that the input tray 42 of the ADF 41 (FIG. 2) is empty, the ROM 106 executes a return to the idle routine. Otherwise, until an address card or a pause card is encountered, as indicated at 276, the ROM 106 repeatedly recycles to alternatelysupply the feed and scan instruction 213 and a incrernent docurnent counter instruction 276. Another document is fed from the input tray 42 of the ADF 41 inresponse to each feed and scan instruction 2137 and a count for the recall memory entry currently being made is incremented by one in response to each incrernent counter instruction 277. Suitably, the increment counter instruction 277 is executed in response to the transition in the logic level of the 8SCAN signal applied to the l/O device 112 (FIG. 14) which occurs whenever a document is fed out of the ADF input tray 42. As will be seen, when an address card or pause card is encountered, the ROM 106 advances to the scan and read instruction 262, and - ~4 -.
~3~

then another rec~ll entry is rnade if necessqry.
Typical Iy, a predetermined number of adjacent addresses within the recall memory section of the RAM 108 are used for each recall entry. For example, if e~ch recall entry rnay be allotted a sufficient number of RAM
c ddresses to store up to twelve telephone number related digits or codes, an operating mo~ie representation, and a document count.
Recall entries may be called up for separate display on the display 92 by depressing the "RECALL" key on the keyboard 36 when the ROM 106 is performing its idle loop routine, as indicated at 281. Depressing the "RECALL" key causes the ROM 106 to issue an instruction 282 for transferring the first recall entry from the recall memory section of the RAM~lû8 to the active data storage section~ When the next display instruction 283 is given, that recall entry will be read out on the displqy 92.
A predetermined count is loaded into the counter 161 when the "RECALL" key is depressed to mark the start of a predetermined time out period, C13 indicated at 284. If the "ERASE" key on the keyboard 36 is depressed before that period expires, the recall entry currently being displayed is erased and all other recall entries are shifted down one location in the recall memory section of - the RAM 108. Moreover, a new time out period is initiated cnd another transfer instruction 285 is given to initicte a display of the next recall entry in line. If, on the other hand, the "ERASE" key is not depressed before the time out period expires but the "RECALL" key is, the display of the next recall entry in line isinitiated by the transfer instruction c8S, but the preceding entry is retained in the recall memory section of the RAM 108. Finally, if neither the "RECAEL" key not the "ERASE" key is operated before the time out occurs, the ROM 106 returns to its idle loop routine.
Vl. CONCLUSION
In view of the foregoing~ it will now be understood that an automqtic telephone dialer which is particular!y well suited for use with facsim.le terminals and the like has been provided.

Claims (5)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In combination with a telephone linked commun-ications terminal having a raster input scanner, and an automatic dialer means for placing outgoing telephone calls from said terminal in response to dialing control instruct-ions identified by mark sense indicia entered on address cards read by said scanner; the improvement comprising storage means for storing data identifying any jobs aborted by said automatic dialer means, and data generating means coupled between said scanner and said storage means for generating at least a part of said data in response to a video output signal supplied by said scanner whenever an address card is being scanned.

2. The improvement of claim 1 wherein said data isolates a reason for the job abort.

3. The improvement of claim 2 wherein said data is stored in successive addresses of a recall memory;
and further including a display, and command responsive means for recalling said data job-by-job from said recall memory for display on said display.

4. The improvement of claim 3 wherein said terminal is a facsimile terminal, and said data includes for each aborted job indicia representing any telephone number digits and terminal control commands unambiguously identified by mark sense indicia entered on address cards associated with said aborted jobs.

5. The improvement of claim 4, wherein said raster input scanner is further utilized whenever said facsimile terminal is operating in a transmit mode to serially convert graphic information carried by a subject copy into a video signal for transmission to another terminal.