DE4101647A1 - Encoded digital data presentation on opto-electronic display matrix - storing occupied sites of rows and addressing display generator memory at corresp. positions - Google Patents

Abstract

The display elements of an LCD matrix (10) are addressed by multiplex drivers (16,18,20), each assigned to a particular area. ASCII or similar data are entered (32) into a memory (12) beginning with the top left matrix element and working along the rows. A character set table is stored in another memory (14) whose output data, in combination with order numbers of display position coordinates, are written into the drivers (16,18,20) by control logic (24) operating an output field storage circuit (28,30). ADVANTAGE - Time lapse between input of data to the matrix and their optical presentation reduced.

Description

The invention relates to a method for representing digitally encoded data as characters on data lines one opto-electronic display matrix according to the generic term of claim 1.

To characters with a better resolution than it was with eight or sixteen segment ads is possible to display pixel matrix displays have been developed. These allow z. 5 x 7 or 7 x 10 pixels to approximate practically all conceivable characters. So all 96 ASCII characters and another 32 Play special characters differently.

In addition to display modules for a single character, there are  also graphic display fields for an optional graphic Representation or a character representation in several Rows of data. Because of the multitude of lines that arise Not every single one of the matrix ads Element a connector led out, but they will also electrically connected as a matrix. However it is this does not allow all necessary items turn on at the same time. The ad is therefore in Time division multiplexed by selecting row by row and the desired combination of display elements is switched on.

If the transfer takes place quickly enough, gives the viewer the impression that everyone is turned on switched elements are active at the same time. Indeed the multiplex rate must not be too high either otherwise the contrast of the display, in particular with LCD displays, decreases.

However, the display elements advance through not the only time factor between queuing digitally encoded data, e.g. B. ASCII data and their Representation as characters on the display matrix. In addition comes the conversion of the digitally encoded data Time needed in a pixel representation as well as the time  for serial transmission in buffers. This can cause that between entering data and their Perceptual display of characters on the display matrix clear response time occurs.

The invention is based, with one Process for the representation of digitally coded data as Characters on data lines of an opto-electronic Display matrix the time between waiting in line Data at the input of the display matrix and its optical Shorten representation.

This task is carried out in a procedure according to the Oberbe handle of claim 1 indicated in the indicator Features resolved.

The invention uses the knowledge that the time to Convert the digitally encoded data into a pixel dar position can be significantly reduced if the Contents of the memory locations of a display data memory not for all conceivable positions on the display measure trix, but only for that Positions at which characters are to be displayed.

To do this with little circuitry and  Being able to spend time is for everyone on the Display matrix of data line to be displayed, the document status determined and saved. Under consideration of then only used parts of a data line Data converted into a pixel representation which occupied positions and intermediate positions assigned to a data line. Leading and Succession there are no empty spaces.

Because in the course of converting data into a pixel dar also a serial transmission in between memory must be done by reducing the number of the conversions at the same time the serial too transferred amount of data reduced, so that with this Measure always made two profits at the same time adding time components. The total achievable time saving is greater, the smaller the Occupancy of a data line.

It is particularly useful to add the first and last plus to save one occupied position of a data line, because in in this case only two more memory locations per Data line are required and the logical link when addressing the character generator memory then very easy to implement  is.

When entering data using a keyboard, further acceleration of the display can be achieved by the content of the storage space just described the display data memory simultaneously with the characters generator memory addressed and only this when changed Character in which drivers are written. In this case is the memory location corresponding to the cursor position of the display data memory with the address input of the Character generator memory connected.

There is also the possibility of spending the time serial transmission of the data to describe the Driver for the segments of the display matrix in dependent to reduce the number of characters to be displayed. this will achieved in that when changing the content of a Storage space or several storage spaces of the display data memory, only those drivers are rewritten which segments of the display matrix on the Go to the position of the characters to be changed.

Particular problems arise with a display matrix, their format from segment rows and segment columns a character position of the format of the character genera  tors deviates. An immediate takeover of the pixel data this character generator would falsify the Characters on the display matrix. To make this mistake eliminate those from the display data memory and Character generator memory adjusted data output first and then written in the drivers.

In order to keep the time required for this implementation to a minimum, becomes an output table with the output data containing memory addressed, which in turn the Driver describes. A time consuming calculation of the relevant segments can therefore be omitted.

The invention further relates to a display device for Representation of digitally coded data as characters Data lines according to an opto-electronic display matrix the preamble of claim 7.

In this regard, it is based on the task of a Display device for displaying digitally coded Data as characters on data lines of an opto-elektroni display matrix the time between waiting in line of data at the input of the display matrix and its shorten visual representation.  

This task is performed on a display device according to the Preamble of claim 1 by the in the mark specified features solved.

Further developments and advantageous refinements of the The method and the display device result from the claims, the further description and the Drawing based on the procedure and the display direction is explained.

The drawing shows:

Fig. 1 is a block diagram of a device and device

Fig. 2 memory tables 1 to 5 for demonstrating the data processing in the display device.

The display device shown in FIG. 1 comprises an opto-electronic display matrix 10 configured as an LCD display. Their display elements are electrically connected as a matrix and can be controlled in multiplex mode via drivers 16 , 18 , 20 . The matrix is divided in such a way that a driver 16 ; 18 ; 20 is only responsible for a certain area.

Furthermore, the display device comprises a display data memory 12 , a character generator memory 14 addressable therefrom, an occupancy memory 22 , an adaptation circuit 26 and control logic 24 . The adaptation circuit 26 in turn consists of a memory 28 containing an output table 4 and an output field memory 30 .

The data pending at a data input 32 , e.g. B. ASCII data first go to the display data memory 12 and are gradually stored there on storage locations. When data is entered via a keyboard and the display data memory 12 is initially empty, the memory location which is assigned to the upper left character position on the display matrix 10 is first addressed and written. Then the next and then the following is described until a data line Z is full. In the case of a multi-line display, it is then the turn of the memory locations that are assigned to the positions in the second line and so on.

The storage locations are selected by means of the control logic 24 , which advances the addressing by one location after each stored data byte or also by cursor control signals which address a specific storage location of the display data memory 12 without data input, which is indicated on the display matrix 10 by a displacement of the position pointer (Cursor) on a certain position.

A character generator carries out the conversion of the stored data into a pixel representation. This consists of the character generator memory 14 , which contains a character set table 3 of all representable pixel-oriented characters and is gradually addressed by the data stored in the display data memory 12 . The output data of this character generator memory 14 thus specify the pixel character corresponding to the data used as address data and the storage space of the display data memory 12 indicates the position of this character on the display matrix 10 .

The position coordinates corresponding to the ordinal numbers of the memory locations of the display data memory 12 are written into the drivers 16 , 18 , 20 in combination with the output data of the character generator memory 14 . This process is also controlled by the control logic 24 . The drivers 16 , 18 , 20 described with this data in turn generate pulse sequences which are applied to the individual row and column feed lines of the display segments and are periodically switched on. This switches on the desired combinations of display elements and makes the characters to be displayed optically visible.

The procedure described so far also corresponds to that common matrix ads. However, these have the Property that after every new entry of a data byte the total memory content of the display data memory again converted by the character generator and into the Driver is registered. This leads to a display measure trix from z. B four lines of data, each with 20 digits, a total of 80 digits, one perceptible Reaction time.

In order to reduce this tent, the first and last plus 1 occupied position of each data line Z are stored in the occupancy memory 22 in the display device according to the invention. In most display cases, not all positions S of a patent cell Z or the entire display matrix 10 are occupied. Taking into account the positions stored in the occupancy memory 22 , the control logic 24 then causes only the memory contents of the display data memory 12 to be converted from the first to the last occupied position of each line. This eliminates the conversion time otherwise required for leading and subsequent empty spaces, whereby the updating of the display matrix 10 , in particular with only a few occupied spaces S, is considerably accelerated.

To clarify the mode of operation, reference is made to FIG. 2. There is a field corresponding to the memory locations of the display data memory 12 according to Table 1, consisting of four data lines with 20 digits each. The storage locations are arranged two-dimensionally and correspond to the representation on the display matrix 10 in the correct row and position. To the right of this table 1, the storage locations of the occupancy memory 22 are illustrated as table 2. It can be seen that two storage locations are provided for each data line.

The display data memory 12 has the following assignment: Positions 0 to 19 are assigned in the first data line, the second line is empty, position 18 is assigned in the third data line and positions 7 and 8 are in the fourth data line.

This leads to the following entries in the occupancy memory 22 : The left column indicates the first occupied position of the data cell in question, the right column the last occupied position plus one, that is the position following the last occupied position. The empty data cell is an exception. Both digits are specified here with 0. Thus the entry for the first line is 1 , 20 ; 0, 0 for the second line , 18 , 19 for the third line and 7 , 9 for the fourth line.

Table 3 in FIG. 2 furthermore illustrates the mode of operation of the character generator memory 14 . This contains a character set table of all representable characters. The characters are 8 x 7 pixels in size. Should z. B. the data byte stored in position 4 of table 1 in the first data line, which contains the value A encoded, is converted, the character generator memory 14 is addressed with this data byte and gives the bytes 00 , 7 I, 11 , 11 , 11 , 7 E, 00 . If the content of the bytes is shown in binary form in columns next to one another, the bit structure represents the letter A as a pixel representation.

The control logic 24 is further configured so that when the content of a memory location of the display data memory 12 changes or the character generator memory 14 is addressed simultaneously or subsequently with this content and only the changed character is written into the drivers 16 , 18 , 20 . When the data is entered via a keyboard, this leads to a virtually delay-free display on the display matrix 10 .

In addition, the control logic 24 takes the memory content of the occupancy memories 22 into account when writing the output data into the drivers 16 , 18 , 20 . This only changes in the data lines Z in which data is entered. In addition, the occupancy memory 22 specifies which areas of the matrix display 10 are required. This enables the control logic 24 to only change those drivers 16 when the data changes; 18 ; 20 to select, which must be rewritten in order to be able to control the corresponding segments of the display matrix 10 at the position of the characters to be changed.

The block diagram in FIG. 1 also takes into account the possibility of being able to control a display matrix 10 whose format of segment rows and segment columns at a character position differs from the format of the character generator memory 14 . The adaptation circuit 26 , comprising the memory 28 containing an output table 4 and the output field memory 30 , adapts the pixel data of the character generator. The data from the output field memory 30 is then written into the drivers 16 , 18 , 20 .

Tables 4 and 5 illustrate the operation of the matching circuit 26 . Table 4 contains an assignment between the characters generated by the character generator memory 14 in pixel representation in connection with the position on the display matrix 10 to the memory locations in the output field according to Table 5. The memory locations in the output field are in turn the segments of the display -Matrix 10 assigned in their respective layout.

Claims (12)

1. A method for displaying digitally coded data as characters on data lines of an optoelectronic display matrix, the coded data first being stored in memory locations of a display data memory which are addressed in accordance with the position of the characters to be displayed on the display matrix be addressed simultaneously or subsequently from the stored data memory locations of a character generator memory and then data output from the display data memory and character generator memory are written to drivers which represent the segments of the optoelectronic display matrix as a function of the characters to be represented Control line by line and column by column in the multiplex, characterized in that the occupied positions of a data line are additionally stored and the character generator memory is addressed from the memory locations of the display data memory which correspond to the occupied positions and the intermediate positions of a D match row. 2. The method according to claim 1, characterized in that that the first and last plus one occupied one Data line is saved and the character generator memory only from the memory locations of the display data memory chers out, the first to last occupied position of a data line. 3. The method according to claim 1 or 2, characterized records that when changing the content of a memory space of the display data memory at the same time or then the character generator memory with this Content is addressed and only the changed character in the driver is written. 4. The method according to one or more of claims 1 to 3, characterized in that when changing the Contents of one or more storage spaces places of the display data memory only those drivers newly described which segments of the display Ma trix at the position of the characters to be changed  head for. 5. The method according to one or more of claims 1 to 4, characterized in that when a Display matrix, its segment rows and segment columns a character position from the segment lines and segment columns of the character generator deviate from the display data memory and character generator memory output Data are adjusted first and then in the driver to be written. 6. The method according to claim 5, characterized in that with the output data an output table containing memory is addressed, which in turn describes the drivers. 7. Display device for displaying digitally coded data as characters on data lines (Z) of an optoelectronic display matrix ( 10 ), which has a display data memory ( 12 ) with memory locations corresponding to the position of the on the display matrix ( 10 ) characters to be displayed, a cher from the display data SpeI (12) addressable character generator memory (14) has a plurality of display data storage (12) and character generator memory (14) recordable drive (16, 18, 20) and one of the drivers (16 18 , 20 ) controlled display matrix ( 10 ), characterized in that in addition an occupancy memory ( 22 ) is provided which stores the occupied positions (S) of a data line (Z) and in that control logic ( 24 ) is provided , by means of which the character generator memory ( 14 ) can be addressed via a logical link between the display data memory ( 12 ) and the occupancy memory ( 22 ) such that it can only be accessed by the memory places of the display data memory ( 12 ) is addressed, which correspond to the occupied positions (S) and the intermediate positions of a data line (Z). 8. Display device according to claim 7, characterized in that the occupancy memory ( 22 ) comprises two storage locations per data line (Z) in which the first and last plus one occupied position (S) of a data line (Z) can be stored. 9. Display device according to claim 7 or 8, characterized in that the address input of the character generator memory ( 14 ) is connected to the output of the memory location of the display data memory ( 12 ), the content of which can be changed and that by means of the control logic ( 24th ) only the changed content of the character generator memory ( 14 ) can be written into the drivers ( 16 , 18 , 20 ). 10. Display device according to one or more of claims 7 to 9, characterized in that by means of the control logic ( 24 ) only those drivers ( 16 , 18 , 20 ) can be selected for describing which segments of the display matrix ( 10 ) at the position assigned to the characters to be changed. 11. Display device according to one or more of claims 7 to 10, characterized in that between the display data memory ( 12 ) and character generator memory ( 14 ) on the one hand and the drivers ( 16 , 18 , 20 ) on the other hand a matching circuit ( 26 ) It is provided which converts the format of segment lines and segment columns of the character generator memory ( 12 ) to the format of the display matrix ( 10 ) at a character position. 12. A display device according to claim 11, characterized in that the adapter circuit ( 26 ) consists of a memory ( 28 ) containing an output table (Tab. 4) and a downstream output field memory ( 30 ).