JPH1191208A - Data converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the change of video data, outputted to a printer engine by a method wherein a converting table, converting a first video data, outputted from a printer controller, into a second video data, is provided in the fore stage of a video interface. SOLUTION: When video data are sent from a host computer into a host I/F(interface) 2, the CPU 1 of a printer controller writes the video data in a RAM 4. Next, the CPU 1 reads the video data out of the RAM 4 and sends the video data to a printer engine through a video transfer circuit 5 and a video I/F 7. A converting table 6 is provided in the video transfer circuit 5 and the video data, read out of the RAM 4, are converted based on the converting table 6. On the other hand, when the gradation or the resolution of the printer engine is changed, the CPU 1 rewrites the contents of the converting table 6 based on the gradation or resolution after the changing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data conversion apparatus for a printing apparatus, and more particularly, to a data conversion apparatus suitable for application when converting resolution and gradation of input print data and outputting the converted data.

[0002]

2. Description of the Related Art In a conventional printing apparatus, data of a printer controller and data of a printer engine sometimes have different resolutions and gradations. For this reason, a plurality of output conversion circuits are provided in the video data output section of the printer controller, and the output conversion circuits are switched and used according to the resolution and gradation of the printer engine.

FIG. 5 is a diagram showing a configuration of a conventional output conversion circuit. In FIG. 5A, the output conversion circuit 41 is 1
When one dot of video data is input from the RAM side, the input one-dot video data is output to the engine side.

In FIG. 5B, an output conversion circuit 42 performs a 2-dot parallel transfer.
When the dot video data is input, the input 2 dot video data is output to the engine side.

In FIG. 5C, an output conversion circuit 43 performs 4-dot parallel transfer.
When the dot video data is input, the input 4-dot video data is output to the engine side.

In FIG. 5D, an output conversion circuit 44
Is output with a bit indicating the presence or absence of a dot added to the 4-gradation data. When 4-gradation video data is input from the RAM side, the input 4-gradation video data is sent to the engine side. In addition to the output, data indicating the presence or absence of a dot is added and output.

In FIG. 5 (e), an output conversion circuit 45
Converts the data of four gradations to the data of two gradations and outputs the data. When the video data of four gradations is inputted from the RAM side, the video data of two gradations is outputted to the engine side and And data indicating the presence or absence of a dot is output.

As described above, the conventional printing apparatus is provided with a plurality of output conversion circuits 41 to 45 corresponding to the data transfer speed, gradation, resolution, etc., and these output conversion circuits 41 to 45 are provided.
, The video data sent from the RAM side is output to the engine side.

[0009]

However, in the conventional printing apparatus, a plurality of output conversion circuits 41 to 45 are provided in the video data output section in accordance with the resolution and gradation, and these output conversion circuits 41 to 45 are provided. I used it after switching
When various specifications are changed or added (for example, the arrangement of bits of the video signal is changed), it is necessary to correct the output conversion circuits 41 to 45, and there is a problem that the hardware must be changed. .

An object of the present invention is to provide a data conversion device capable of easily changing video data output to a printer engine.

[0011]

According to the present invention, a conversion table for converting first video data output from a printer controller into second video data is provided by a video interface. Is provided at the preceding stage.

Thus, the video data output to the printer engine can be changed only by referring to the conversion table. Even when the video data is output to a printer engine having different gradations and resolutions, There is no need to change hardware.

Further, according to one aspect of the present invention, there is provided rewriting means for rewriting the contents of the conversion table. This makes it easy to respond to changes and additions to the specifications of gradation and resolution simply by rewriting the contents of the conversion table. Even if it changes, there is no need to change the hardware,
The convenience of the printing apparatus can be improved.

Further, according to one aspect of the present invention, the conversion table includes a storage unit for storing the second video data, and a second table stored in the storage unit based on the first video data. Selecting means for selecting video data.

This makes it possible to convert the first video data to the second video data only by selecting the second video data, and to convert the video data output from the printer controller to the level of the printer engine. It is possible to easily output according to the key and resolution.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A data converter according to one embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing a schematic configuration of a printer controller according to one embodiment of the present invention. In FIG.
When the video data is sent from the host computer to the host interface 2, the CPU 1 writes the video data sent from the host computer into the RAM 4. Then, the CPU 1 reads the video data from the RAM 4 and sends the read video data to the video transfer circuit 5. The video transfer circuit 5 sends video data to the printer engine via the video interface 7.

Here, a conversion table 6 is provided in the video transfer circuit 5, and based on the conversion table 6, RA
Conversion of the video data read from M4 is performed.
As a result, the video data read from the RAM 4 is
It is possible to adapt to the gradation and resolution of the printer engine.

When the gradation and resolution of the printer engine are changed, the CPU 1 rewrites the contents of the conversion table 6 based on the changed gradation and resolution. As a result,
The contents of the conversion table 6 can be adapted to the gradation and resolution of the printer engine without changing the hardware, and it is possible to easily cope with various changes and additions of the specifications of the printer engine. .

FIG. 2 is a block diagram showing a configuration example of the video transfer circuit of FIG. In the configuration of FIG.
4 to the video transfer circuit 5 are 32-bit parallel, the data input to the conversion table 6 are 4-bit parallel, and the data output from the conversion table 6 are 6-bit parallel.

In FIG. 2, first, the contents of the conversion table 6 are set in accordance with the gradation and resolution of the printer engine. When setting the contents of the conversion table 6, the CPU 1
Sends a conversion table set signal to the conversion table 6,
The conversion table 6 is set in a rewritable state. And
When the conversion table 6 is in a rewritable state, the CPU 1
Sends the rewrite data to the conversion table 6,
The contents of the conversion table 6 are rewritten.

Next, the CPU 1 sets how many bits the data input to the video transfer circuit 5 is shifted per clock. When setting the shift amount of the input data, the CPU 1 sends a shift amount set signal to the shift amount latch circuit 15 so that the shift amount can be set in the shift amount latch circuit 15. Then, the CPU 1 sends the shift amount of the input data to the shift amount latch circuit 15 so that the shift amount latch circuit 15 latches the shift amount. The shift amount latched by the shift amount latch circuit 15 is output to the shift register 12. Shift register 12
Outputs the data to the conversion table 6 while shifting the input data based on the shift amount output from the shift amount latch circuit 15.

For example, when the video transfer circuit 5 performs serial transfer of one dot to the printer engine, the shift amount of the shift amount latch circuit 15 is set to 1 (one bit shift by one clock), and the video transfer circuit 5 When performing 2-dot parallel transfer to the printer engine, the shift amount of the shift amount latch circuit 15 is set to 2 (2-bit shift by one clock), and the video transfer circuit 5 transmits 4-dot parallel transfer to the printer engine. In this case, the shift amount of the shift amount latch circuit 15 is set to 4 (4 bits are shifted by one clock).

When transferring input data read from the RAM 4 to the printer engine, the CPU 1
1 and the latch circuit 11 latches the input data read from the RAM 4. Latch circuit 11
Sends the latched input data to the shift register 12. In the shift register 12, the data is loaded at the head of the video data output. Then, in synchronization with the clock signal, the input data is output to the conversion table 6 while being shifted by the shift amount output from the shift amount latch circuit 15.
Here, assuming that the shift amount of the shift amount latch circuit 15 is set to 4, the input data is output to the conversion table 6 while being shifted by 4 bits. When the shift of the 32-bit data latched by the latch circuit 11 is completed, the next data is loaded.

When 4-bit data is sent from the shift register 12, the conversion table 6 converts the 4-bit data into 6-bit data and outputs the converted data to the latch circuit 14. When the 6-bit data is sent from the conversion table 6, the latch circuit 14 latches the 6-bit data in synchronization with the clock signal. The data latched by the latch circuit 14 is sent to the printer engine via the video interface 7.

FIG. 3 is a block diagram showing a configuration example of the conversion table 6 of FIG. In FIG. 3, sixteen 6-bit latch circuits 20 to 35 and a selector 36 for selecting outputs of the latch circuits 20 to 35 are provided.

When writing data to the conversion table shown in FIG. 3, the CPU 1 operates the latch circuits 20 to
35-bit data is set. For example, when data is set in the latch circuit 20, a 6-bit data is latched in the latch circuit 20 by sending a table write signal to the latch circuit 20. Also, the latch circuit 21
When the data is set in the latch circuit 21, a 6-bit data is latched in the latch circuit 21 by sending a table write signal to the latch circuit 21. Thus, the latch circuit 20
To set data in the conversion table, the table write signal is sent to the latch circuits 20 to 35 that set the data, and the data is latched by the latch circuits 20 to 35 that have sent the table write signal. I do.

When performing data conversion using the conversion table shown in FIG. 3, the selector 36 determines the latch circuit 2 based on the 4-bit data output from the shift register 12.
Select outputs 0-35. When the output of the latch circuits 20 to 35 is selected by the selector 36, the 6-bit data latched by the selected latch circuits 20 to 35 is sent to the printer engine via the video interface 7.

As described above, by selecting the latch circuits 20 to 35 and outputting the data, the video data read from the PAM 4 can be converted and output to the printer engine.

Also, by rewriting the contents of the latch circuits 20 to 35 in accordance with the gradation and resolution of the printer engine, the video data read from the RAM 4 is output in accordance with the gradation and resolution of the printer engine. It is possible to do.

FIG. 4 is a diagram showing an example of the contents of the conversion table of FIG. 2. FIG. 4A shows that the input is 1 bit / pix,
This shows the configuration of the conversion table 6 when the output is 1 bit / pix. In FIG. 4 (a), 1 is connected to the D0 terminal.
When the bit data is input, the 1-bit data input to the D0 terminal is output from the V0 terminal as it is.
The inputs of the D1 to D3 terminals are connected, but the values of the table are determined so that 0 or 1 may be set.
Terminal is open (not used as VIDEO signal)
To be.

The contents of the conversion table 6 in FIG. 4A are, for example, (D3, D2, D1, D0) = (0, 0, 0,
0), (V5, V4, V3, V2, V1, V
0) = (0,0,0,0,0,0) is set, and (D
(D5, V4, V3, V2, V1, V0) = (0, 3, D2, D1, D0) = (0, 0, 0, 1)
0, 0, 0, 0, 1) are set. That is, 16 types of (V5, V4, V3, and V3) corresponding to (a) in the table of FIG.
V2, V1, V0) are the latch circuits 20 to 35 of FIG.
Are set respectively. And (D3, D2, D1,
When the value of (D0) is supplied from the shift register 12 of FIG. 2 to the selector 36 of FIG. 3, (D3, D2, D1, D0)
Are selected by the selector 36, and the values of (V5, V4, V3, V2, V1, V0) stored in the latch circuits 20 to 35 are:
The data is sent to the printer engine via the video interface 7.

For example, (V5, V4, V3, V2, V
(0, 0, 0, 0, 0, 0) is set in the latch circuit 20 as (1, V0), and (V5, V4, V3, V2, V
It is assumed that (0, 0, 0, 0, 0, 1) is set in the latch circuit 21 as (1, V0), and the selector 36
Selects (0, 0, 0, 0) when (0, 0, 0, 0) is sent from the shift register 12, and selects the latch circuit 20.
When 1) is sent from the shift register 12, the latch circuit 21 is selected. In this case, (D3, D
When (0, 0, 0, 0) is supplied from the shift register 12 to the selector 36 as (2, D1, D0), (0, 0, 0, 0)
0,0,0,0,0) is sent to the printer engine,
(D3, D2, D1, D0) as (0, 0, 0,
When 1) is supplied from the shift register 12 to the selector 36, (0, 0, 0, 0, 0, 1) is sent to the printer engine.

FIG. 4B shows that the input is 4 bits / pix,
It shows the configuration of the conversion table 6 in the case where the output is 4 bits / pix and the data presence / absence bit is added by one bit (V0 bit). In FIG. 4B, when 4-bit data is input to the D0 to D3 terminals, the 4-bit data input to the D0 to D3 terminals is directly output from the V1 to V4 terminals. Further, when the 4-bit data input to the D0 to D3 terminals are all 0, 0 is output from the V0 terminal, and when any one of the 4-bit data input to the D0 to D3 terminals is 1, V0 is output. 1 is output from the terminal. The V5 terminal is open (VIDEO
Not used as a signal).

The contents of the conversion table 6 in FIG. 4B are, for example, (D3, D2, D1, D0) = (0, 0, 0,
0), (V5, V4, V3, V2, V1, V
0) = (0,0,0,0,0,0) is set, and (D
(D5, V4, V3, V2, V1, V0) = (0, 3, D2, D1, D0) = (0, 0, 0, 1)
0, 0, 0, 1, 1) are set. That is, 16 types of (V5, V4, V3, and V3) corresponding to (b) in the table of FIG.
V2, V1, V0) are the latch circuits 20 to 35 of FIG.
Are set respectively. And (D3, D2, D1,
When the value of (D0) is supplied from the shift register 12 of FIG. 2 to the selector 36 of FIG. 3, (D3, D2, D1, D0)
Are selected by the selector 36, and the values of (V5, V4, V3, V2, V1, V0) stored in the latch circuits 20 to 35 are:
The data is sent to the printer engine via the video interface 7.

For example, (V5, V4, V3, V2, V
(0, 0, 0, 0, 0, 0) is set in the latch circuit 20 as (1, V0), and (V5, V4, V3, V2, V
It is assumed that (0, 0, 0, 0, 1, 1) is set in the latch circuit 21 as (1, V0), and the selector 36
Selects (0, 0, 0, 0) when (0, 0, 0, 0) is sent from the shift register 12, and selects the latch circuit 20.
When 1) is sent from the shift register 12, the latch circuit 21 is selected. In this case, (D3, D
When (0, 0, 0, 0) is supplied from the shift register 12 to the selector 36 as (2, D1, D0), (0, 0, 0, 0)
0,0,0,0,0) is sent to the printer engine,
(D3, D2, D1, D0) as (0, 0, 0,
When 1) is supplied from the shift register 12 to the selector 36, (0, 0, 0, 0, 1, 1) is sent to the printer engine.

FIG. 4C shows that the input is 2 bits / pix,
This shows the configuration of the conversion table 6 in the case where the output is 4 bits / pix and one bit of data presence / absence is added (V0 bit). This conversion table 6 has four gradation values (2
bit / pix) to 16 gradation values (4 bit / pix)
Is assigned to In FIG. 4C, when 2-bit data is input to the D0 and D1 terminals, V1 to V1 are input.
4-bit data is output from the V4 terminal. here,
As a method of changing the value of 4 gradations to the value of 16 gradations, (D1,
D0) = (0,0), (V4, V3, V2, V
1) = (0,0,0,0) and (D1, D0)
= (0,1), (V4, V3, V2, V1) =
(0,1,0,1) and (D1, D0) =
For (1, 0), (V4, V3, V2, V1) =
(1, 0, 1, 1), and (D1, D0) =
For (1, 1), (V4, V3, V2, V1) =
(1, 1, 1, 1) is assigned.

Also, 2b input to the D0 and D1 terminals
When all the data of it is 0, 0 is output from the V0 terminal, and when any one of the 2-bit data input to the D0 and D1 terminals is 1, 1 is output from the V0 terminal. The inputs of the D2 and D3 terminals are connected, but the values of the table are determined so that they may be 0 or 1.
The V5 terminal is left open (not used as a VIDEO signal).

The contents of the conversion table 6 in FIG. 4C are, for example, (D3, D2, D1, D0) = (0, 0, 0,
0), (V5, V4, V3, V2, V1, V
0) = (0,0,0,0,0,0) is set, and (D
(D5, V4, V3, V2, V1, V0) = (0, 3, D2, D1, D0) = (0, 0, 0, 1)
0, 1, 0, 1, 1) are set. That is, 16 types (V5, V4, V3, and V3) corresponding to (c) in the table of FIG.
V2, V1, V0) are the latch circuits 20 to 35 of FIG.
Are set respectively. And (D3, D2, D1,
When the value of (D0) is supplied from the shift register 12 of FIG. 2 to the selector 36 of FIG. 3, (D3, D2, D1, D0)
Are selected by the selector 36, and the values of (V5, V4, V3, V2, V1, V0) stored in the latch circuits 20 to 35 are:
The data is sent to the printer engine via the video interface 7.

For example, (V5, V4, V3, V2, V
(0, 0, 0, 0, 0, 0) is set in the latch circuit 20 as (1, V0), and (V5, V4, V3, V2, V
(0, 0, 1, 0, 1, 1) are set in the latch circuit 21 as (1, V0), and the selector 36
Selects (0, 0, 0, 0) when (0, 0, 0, 0) is sent from the shift register 12, and selects the latch circuit 20.
When 1) is sent from the shift register 12, the latch circuit 21 is selected. In this case, (D3, D
When (0, 0, 0, 0) is supplied from the shift register 12 to the selector 36 as (2, D1, D0), (0, 0, 0, 0)
0,0,0,0,0) is sent to the printer engine,
(D3, D2, D1, D0) as (0, 0, 0,
When (1) is supplied from the shift register 12 to the selector 36, (0, 0, 1, 0, 1, 1) is sent to the printer engine.

FIG. 4D shows that the input is 2 bits / pix,
The output is 2 bits / pix, video data is transferred in 2 pix parallel, and data presence / absence bits are added to each pixel data by one bit (V0
3 shows the configuration of the conversion table 6 in the case of a bit (V3 bit). In FIG. 4B, when 4-bit data is input to the D0 to D3 terminals, the first pix gradation data is output from the V1 and V2 terminals, and
The second pix gradation data is output from the fourth and V5 terminals.

Further, 2b input to the D0 and D1 terminals
When all the data of it is 0, 0 is output from the V0 terminal, and when any one of the 2-bit data input to the D0 and D1 terminals is 1, 1 is output from the V0 terminal. Further, 2bi input to the D2 and D3 terminals
When the data of t is 0, 0 is output from the V3 terminal. When at least one of the 2-bit data input to the D2 and D3 terminals is 1, 1 is output from the V3 terminal.

The contents of the conversion table 6 in FIG. 4D are, for example, (D3, D2, D1, D0) = (0, 0, 0,
0), (V5, V4, V3, V2, V1, V
0) = (0,0,0,0,0,0) is set, and (D
(D5, V4, V3, V2, V1, V0) = (0, 3, D2, D1, D0) = (0, 0, 0, 1)
0, 0, 0, 1, 1) are set. That is, 16 types (V5, V4, V3, and V3) corresponding to (d) in the table of FIG.
V2, V1, V0) are the values of the latch circuits 20 to 35 in FIG.
Are set respectively. And (D3, D2, D1,
When the value of (D0) is supplied from the shift register 12 of FIG. 2 to the selector 36 of FIG. 3, (D3, D2, D1, D0)
Are selected by the selector 36, and the values of (V5, V4, V3, V2, V1, V0) stored in the latch circuits 20 to 35 are:
The data is sent to the printer engine via the video interface 7.

For example, (V5, V4, V3, V2, V
(0, 0, 0, 0, 0, 0) is set in the latch circuit 20 as (1, V0), and (V5, V4, V3, V2, V
It is assumed that (0, 0, 0, 0, 1, 1) is set in the latch circuit 21 as (1, V0), and the selector 36
Selects (0, 0, 0, 0) when (0, 0, 0, 0) is sent from the shift register 12, and selects the latch circuit 20.
When 1) is sent from the shift register 12, the latch circuit 21 is selected. In this case, (D3, D
When (0, 0, 0, 0) is supplied from the shift register 12 to the selector 36 as (2, D1, D0), (0, 0, 0, 0)
0,0,0,0,0) is sent to the printer engine,
(D3, D2, D1, D0) as (0, 0, 0,
When 1) is supplied from the shift register 12 to the selector 36, (0, 0, 0, 0, 1, 1) is sent to the printer engine.

In addition to these, various variations can be converted by setting the table. Further, according to such a table conversion method, even when the arrangement of the VIDEO signals of the video interface 7 is changed, it is possible to cope with the change only by rewriting the contents of the conversion table 6.

As described above, in the video interface 7 of the printer controller, by providing the conversion table 6 in the output section, the case where the resolution or gradation of the printer engine changes, the specification or arrangement of video data bits changes. In this case, the same printer controller can easily cope with such a case.

Also, in the video interface 7 of the printer controller, a conversion table is provided at the output section and can be freely rewritten by a program, so that the specification of resolution and gradation and the arrangement of signals can be changed. It can be easily handled.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various other modifications can be made within the technical idea of the present invention. For example, in the above-described embodiment, the case where the conversion table 6 is configured by the plurality of latch circuits 20 to 35 and the selector 36 has been described, but the conversion table 6 is configured by a memory of 4 bits of address and 6 bits of output. Is also good.

In the above-described embodiment, the conversion table 6 has been described as having four input bits and six output bits. However, the input and output bit widths of the conversion table 6 may be arbitrary. Further, in the above-described embodiment, the output (data on the same line) from one shift register 12 is input to the conversion table 6, but the output (multiple lines) from a plurality of shift registers is input to the conversion table 6. You may make it.

[0049]

As described above, according to the present invention,
By providing a conversion table in the preceding stage of the video interface, it is possible to change video data to be output to the printer engine only by referring to the conversion table, and to output data to a printer engine having a different gradation and resolution. Also, there is no need to change hardware.

Further, according to one aspect of the present invention, by making the contents of the conversion table rewritable, it is possible to easily cope with a change or addition of gradation and resolution specifications. Even when addition occurs or when the arrangement of bits of the video signal changes, the hardware does not need to be changed, so that the convenience of the printing apparatus can be improved.

Further, according to one aspect of the present invention, by selecting and outputting video data stored in the storage means, it is possible to easily convert the video data, and to output the video data from the printer controller. Video data corresponding to the gradation and resolution of the printer engine.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a printer controller according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a video transfer circuit in FIG. 1;

FIG. 3 is a block diagram illustrating a configuration example of a conversion table in FIG. 2;

FIG. 4 is a diagram showing an example of the contents of a conversion table in FIG. 2;

FIG. 5 is a diagram showing a configuration of a conventional output conversion circuit.

[Explanation of symbols]

 Reference Signs List 1 CPU 2 Host interface 3 ROM 4 RAM 5 Video transfer circuit 6 Conversion table 7 Video interface 11, 14 20-35 Latch circuit 12 Shift register 15 Shift amount latch circuit 36 Selector

Claims (3)

[Claims] A video interface for outputting video data from a printer controller to a printer engine; and a video interface provided before the video interface;
A conversion table for converting first video data output from the printer controller into second video data. 2. The data conversion device according to claim 1, further comprising a rewriting unit that rewrites the contents of the conversion table. 3. The conversion table includes: a storage unit that stores the second video data; and a selection unit that selects second video data stored in the storage unit based on the first video data. 3. A data conversion device for a printing apparatus according to claim 1, further comprising: means.