DE1901294A1 - Data-controlled character generator - Google Patents

Description

Patent attorney

7 Stuttgart-Feuerbach

Short street 8

Q.M. Gardner 6

STANDARD TEIiEPHONES AND CABLES LIMITED, 190 Strand, LONDON W.C. 2 / ENGLAND

Data-controlled font number generator

The priority of application no. 01728/68 of January 11, 1968 in the UK is claimed.

The invention relates to a data-controlled character generator for controlling a one-dimensional, multi-track recording head for printing units with section-by-section serial recording in the Moeaikraster.

The invention is characterized in that the incoming files are processed by a receiving logic line by line are entered into a memory, from which they are called up one after the other by an address register for evaluation, that via a character section counter only one specific one at a time Section (row) of the character located in the address register is addressed so that this address is stored in a character shape memory is supplied, which on the output side forms the mosaic dot grid of this section and that via distribution means is fed to the portion of the multi-track recording head assigned to the respective character, that in each case the Equivalent, row-by-row sections of all characters belonging to a line are read out one after the other and the corresponding Traces of the recording head are fed and that with each completed section line, the recording medium, preferably printing drum, by one section position across is transported further to the longitudinal direction of the line.

ZEW / P GrPf vHy-krä.

Jan 8, 1969 909835/1274 ~ ² "

On the basis of an exemplary embodiment, the invention is connection with the drawings explained in more detail below.

Fig.l shows a block diagram of a font gen-

rators according to the invention. Fig.2 shows part of the block diagram of Fig.l with a device for varying the spacing between characters.

The character generator according to Fig.l is designed so that in conjunction with a 220-track recording head 14 speeds of up to 80,000 characters per second can be achieved can. It is thus also possible to use this device together with a cathode ray display tube. These Speed corresponds to approximately 4000 lines at 20 characters per second. When the recording head 14 is part of a non-impact printing unit forms, as shown in Fig.l, the characters are as charge images on the surface a printing drum 15 which is rotated by a motor 16. By dusting the charge image with a special one Powder and rolling of the drum surface on one passing the drum at the same speed The powder image is transferred to the paper web. This results in 17 meters of paper per second with 240 print lines per meter. Acquaintance hitting line printers work up to about 1350 Lines per minute.

The basis of this character generator is a high-speed memory 18 with non-destructive readout, e.g. a waffle iron memory, which physically forms a unit. For a better explanation it is assumed that he is in individual Sections is divided, namely in a buffer storage section and a character shape storage section. These sections can be further subdivided.

It is important to have a buffer section for character generation provide in which at least one complete

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Line of characters can be saved if a repeated retransmission is to be avoided. Is just a pointer memory present, it is necessary to replenish this memory during the time that the drum 15 needs to travel a distance equal to the distance between two lines. However, this creates a severe limitation and leads to the fact that the printer must be treated with high priority in a computer system and otherwise requires a high data transmission speed between the printer and a central data processing system.

This situation can be improved to a certain extent by the character generating device according to Pig which two line memories 2 and 3 are provided, which are designed so that one of these line memories is filled from the data source via a receive logic 1 while the data contained in the other line memory are evaluated, e.g. by writing them on a strip of paper to be printed.

The additional line memory increases the cost of the character generator. However, since it increases the size of the memory by only y $> , its impact on the final cost is very little compared to the improvements obtained by its inclusion.

It should be noted, however, that this character generator is not limited to the use of only two line stores, but can store any number of line stores desired be used. For certain applications it may be necessary to provide more than two line memories, e.g. if the Character generator is used together with a non-impact printing unit and / or a display device that has a printing drum that softens at a relatively high speed running around. In this case, in a device which only uses two Zeilerispe icher, the time between the Receipt of the message signal and the printing of the last one

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Line of characters not long enough to stop the print drum at the end of the message flow, so it is necessary to to increase the storage capacity of the device by providing a greater number of line memories. The.additional Storage capacity is to be selected so that the time between the receipt of the message end signal and the Generation of the last character of the message passes, is long enough to stop the drum at the right moment.

The portion of the memory 18 which forms the character shape is formed by a character shape memory 4 which is controlled via a switch SW 3 is connected to receive logic 1.

As can be seen from the drawing after Pig. 1, everyone succeeded incoming data, e.g. originating from a tape reader or arriving via a trunk line, to receive logic 1, which forwards the processed characters to line memory 2 or 3, where they are stored line by line.

In addition, the reception logic 1 recognizes the beginning and the end of each message transmission and shows this through Signals to the printer and possibly the data sources.

The two line memories 2 and j5 change their punctures the control of a switching logic 7 · This can be done from Pig.l can be seen in which, for example, the memory 2 is connected to the data input via a switch SW 1, i.e. via the Contact position 2 of this switch and contact position 1 of the switch SW 3 with the reception logic 1. At the same time, the memory 5 is in the contact position via a switch SW 2 2 connected to an address register 5. The switching logic 7 causes the switches SW 1 and SW 2 to switch over together when the stored line of one line memory and the other line memory has been printed out is filled with the next line to be printed. When this occurs, the line memory j5 is connected to the receiving logic 1 and the line memory 2 with the address register 5. -

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It should be noted that the switches shown in Pig SW 1, SW 2 and SW 3 in a practical electronic version Switching units are formed.

The character shape memory 4 stores the characters in the form in which they are to be printed and which before use must be entered in the facility. The character shape memory 4 must therefore be filled before printing begins. This is done by the data source, via receiving logic 1 and contact position 2 of switch SW 5 When the character shapes are stored, the device is switched to the printing mode, i.e., the switch SW 3 goes to position 1, so that the subsequent incoming data are transferred to line memories 2 and j5, where they are available to select the required character shape for feeding the recording head 14.

The recording head 14 forms the characters on the surface of a printing drum 15 in the form of a charge image which is dotted is constructed. To record the point-like charge image on the drum surface, a line is required to form a line Series of operations necessary. The top row of dots of the first character must be formed first, followed by the top of the second character, etc. After writing the top row of the last character, i.e. the twentieth character for the above-mentioned recording head, the drum 15 be rotated by the motor 16 so that the recording of the second row of points below the first is possible. This The process must be repeated to form a dot matrix of e.g. a maximum of 220 χ 22 points for the 22 rows of points, to form a line with 20 characters from this matrix.

In one possible embodiment of the character generator 4 words with the numbers 0 - 256 are added to the character shape memory and words numbered 257 - J5Q0 are assigned to the line memories. In another embodiment, words with numbers 0 - 300 used in such a way that the second half of the uneven

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numerous words are assigned to the line memories, while the remainder is used for the string shape memory k . These two possibilities show the fact that the same access circuit etc. are used to access all sections of the memory 18.

In the first arrangement, for example, two complete memory words are assigned to each character, and each memory word contains eleven sections, i.e. eleven rows of e.g. eleven points each. Therefore, with this setup, each character is made from a matrix formed from 22 χ 11 points.

The initial writing in the character shape memory 4 is achieved by sequentially feeding in the character sets. if If it is necessary to change a single character, the serial number or numbers of the character concerned must be specified to avoid having to rewrite all characters.

Once the character set has been specified, as already mentioned, it is switched to print mode, i.e. the contact position 1 of the switch SW 3 is selected, whereby the data input is applied to one of the character memories 2 or j5, to a complete line is received. After receipt, the switching logic 7 connects the filled character memory via the Switches SW 1 and SW 2 with the address register 5 and the empty ones Line memory with receive logic 1.

The first character from the filled line memory is given during the printing operation together with the output signal of a character cut-off counter 6 in the address register 5, which specifies the special row of dots of the selected character to be printed, ie the top one at the start of printing - . '■■ - row of points. -. ■ ■

The address register 5 therefore contains after this process' the Address of the character to be pressed along with the

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Information that is necessary to determine the exact storage space of the part of the character to be recorded in the character shape memory h. This memory location is queried and its content is applied to the recording head 14 via appropriate selection circuits.

After recording the top row of dots of the first character the second character is fetched from the line memory and the top row of dots of this character is queried and recorded. This process continues until the top row of dots of the last character in this line, i.e. the twentieth Character was queried and recorded in the example mentioned. The first character of this line is now all over again taken from the line memory and placed in the address register 5. Since the second row of dots of the characters of this line is to be recorded, the character section counter 6 advances by one Unit to mark this second section. This process repeats itself until the characters complete the line are recorded.

The selection circuits through which the contents of the memory are applied to the 220-track recording head 14 exist of storage elements 9, a power amplifier 10, one Diode matrix 11 with e.g. 22 χ 10 storage points, a further power amplifier 12 and a character counter 13

The tracks of the recording head can be in serial can be controlled. In this case, the track and character coordinate switches, which form the character counter 13, identis before streams.

In operation, the character counter 13 causes pulses to the 22 χ 10 diode matrix get through each of ten Output lines, these current impulses through the power amplifier 12 are amplified before they get to the diode matrix. Select the pulses applied to the ten input lines the information coming from the character shape memory 4

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represents part of one of the twenty characters on a line and cause the information to be sent to the recording head 14 via the correct one of the two hundred and twenty input lines reach.

However, this requires that the character counter Γ3 with the character section counter -6 is synchronized to ensure that the query of a string of characters in the character shape memory 4 with the the track of the recording head 14 associated with the character in question coincides. The counter Γ5 therefore always carries one complete orbital cycle, i.e. in coincidence with the occurrence of one character each it sends a current impulse to the matrix 11 via one of the twenty input lines. The impulses are in coincidence with one query pulse each, which are applied to the character shape memory 4.

If it is necessary to change only one character of the font contained in the character shape memory 4 during printing, the logic unit must be ^{switched to the operating mode 'character shape formation 1} , ie in the contact position 2 of the switch SW 3 * and the new character shape according to the Input data are entered. It should be noted, however, that this process must only occur during the time between the lines, since the original character shape may still be required for the previous line.

The main advantage of a memory with non-destructive readout is that the control logic necessary to a perform certain operations can be reduced and that more time is available for read operations, if a read is not followed by a write back. From the above it can be seen that the character generator according to Pig.l causes a point-by-point recording of the characters and that the character shapes that correspond to the coded input signals correspond and are stored in a high-speed memory with non-destructive readout, changed by a program control can be. The form of representation in which incoming

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Signals are printed or displayed can then be changed arbitrarily, e.g. by initiating the data source is to supply a block of character shape signals in preparation for the following text. Known character generators to this day have used hand-wired translation memories which have been rewired or replaced must be used if other character shapes are to be used.

Line adjustment can be important for certain applications to have, so that means must be provided in the character generating device to the distance between the to vary individual characters. In Pig.2 there is now a Block7 Scheme of part of Pig. 1 shown in which agent is present are to change the spacing between characters. With this arrangement, the character shape memory 4 outputs when a Activation takes place, an output signal from which the character form is equivalent to. This signal is fed to a width measuring device 17, in which this signal is converted and is passed to the character counter 13. This is in this one Case designed to count in small steps equal to the center-to-center distance of the mosaic points. So he counts not in fixed character sections, as is the case with the establishment according to Fig.l was the case. The width measuring device 17 gives a signal which is a function of the width of the character memory 4 queried signal is on the character counter 13. This is thereby caused to be an appropriate number of point spacings advance to direct the character data to the corresponding tracks of the recording head 14. Through this it is ensured that the desired spacing between the characters is maintained.

As an alternative solution, the variable character width information can also be provided by the address register 5 together with the width measuring device 17 are formed. In this case the connection between the character shape memory 4 and the width measuring device would be 17 can be omitted and the device 17 can be connected directly to the address register 5. (This connection is shown in Figure 2 as a dashed line). For this

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In the application, the signal called up from the line memory in the address register 5, which is representative of a character, would also contain information about the character width. This information goes to the width measuring device 17 * which
works together with the counter 1 ^>, in the same way as already described, to add the character point markings to the
To guide corresponding tracks of the recording head 14, so that it must also be ensured in this Pail that the desired spacing between the characters is maintained.

The character generator is used in the manner described a single high speed memory with non-destructive readout for the buffer memory section and the character shape memory section. However, it is also possible, albeit not very economically, to have a separate high-speed storage device with non-destructive To use readout for each of these sections and to use separate memories for each of the line memories.

If the use of a high-speed memory with non-destructive readout was assumed in the preceding, so
Of course, a memory with a destructive readout can also be used if care is taken that
If necessary, put the characters back into the
Memory can be written.

4 claims

2 sheets drawing. (2 fig.)

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Claims (4)

Claims 1. Data-controlled character generator for controlling a one-dimensional, multi-track recording head for Printing units with section-by-section serial recording in a mosaic grid, characterized in that the incoming data, from a receiving logic (1) processed, entered line by line into a memory (2 or 3), from which they are successively stored in an address register (5) can be called up for evaluation that a character section counter (6) only has a specific one Section (row) of the character located in the address register (5) is addressed so that this address is stored in a character shape memory (4) is supplied, which is on the output side the mosaic dot grid of this section forms and that via distribution means (9 to 13) the, the respective characters associated portion of the multi-track recording head (14) is supplied that in each case the equal, row-wise sections of all characters belonging to a line read out one after the other and fed to the corresponding tracks of the recording head (14) and that with the recording medium for each completed section line, preferably printing drum (15) j by one segment division each is transported further transversely to the longitudinal direction of the line. 2. Character generator according to claim 1, characterized in that the character shape memory is lehne t (4) can be rewritten and that switching means are provided which allow the memory contents to be rewritten via the receiving line. 3 · Character generator according to claim 1, characterized in that the distribution means in the essentially consist of a diode matrix (11) and a character counter (13) that the diode matrix (11) with the Output of the character shape memory (4) is connected that the character counter (13) wit the character section counter 909835 / 127A - 12 - (6) is synchronized and that the character counter (13) via separate lines one after the other in the manner of the matrix (11) controls how the character shape memory (4) through the character section counter (6) is queried. 4. Character generator according to claim 1, characterized characterized in that two line memories (2 and 3) are provided, which by a switchover logic (7) controlled changeover contacts (SWl and SW2) alternating with the receive logic (l) and the address register (5) to be connected. ZEW / P GrPf vHy-krä.
January 8, 1969 909835/1274 , ^ ³ ■ ♦ Blank page