JPH01168466A - Printer - Google Patents

Abstract

PURPOSE:To achieve reduction of the capacity of a RAM, by a method wherein when an apparatus is initialized on starting-up or the like, address information on each font is written in the RAM. CONSTITUTION:A ROM 4 for storing an operation program and a RAM 5 for performing processes are connected to a CPU 2 via an address bus 3a and a data bus 3b. The RAM 5 has an area to be used as an address information memory and an area to be used as a bit data memory. Further, the CPU 2 is equipped with a bit data writing means for reading a bit data specified by address information stored in the area to be used as the address information memory in the RAM 5 from a CG ROM 7 and writing the bit data in the area to be used as the bit data memory in the RAM 5 according to a font ID inputted from outside, and a printing output means for reading a bit data corresponding to a character data inputted from outside from the area to be used as the bit data memory in the RAM 5 and for printing with a printer 12.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention reads out bit data corresponding to externally input character data from a character generator and performs RA processing.
The present invention relates to a printer that prints out data after once writing to M.

[Conventional technology]

In a conventional printer, when the reset is released during initialization such as when the power is turned on, the CPU starts up and clears internal registers, input ports, etc. Thereafter, when performing initial settings, all bitmap font data is read from the CGROM and stored as bitmap data in the RAM. Then, when printing out, select the bitmap data of the desired character from this RAM,
Printout character data is obtained by editing this.

[Problem that the invention seeks to solve]

The characters stored in the printer's CG ROM are -
It has multiple fonts inside its shell. By the way, the character data of one type of font is approximately several tens of kilobytes in total, and the entire character data stored in the CG ROM has a large amount of data reaching several hundred kilobytes.

Previously, all this data amounting to several hundred kilobytes was stored in C.
G Read from ROM and write to RAM1. : Since it was written, it was necessary to use a large area of RAM to store this character data, and there was a problem that the area used for CPU calculation processing, reception buffer, etc. became small. .

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a printer that can efficiently use RAM capacity a without occupying a large area of RAM by writing all character data in RAM.

[Means for solving problems]

In order to solve the above-mentioned problems and achieve the object, the present invention takes the following measures. In other words, in a printer that reads bit data corresponding to externally input character data from a character generator, once writes it to RAM, and then prints it out, the font I is set for each font type.
D, an address information memory that stores address information consisting of a start address and an end address of bit data of the corresponding font stored in the character generator, and a bit data memory that stores bit data for printing out; Font I input from outside
bit data writing means for reading specified bit data of the address information stored in the address information memory from the character generator and writing it into the bit data memory in accordance with D; and a printout means for reading the bit data from the bit data memory and printing it out.

[Effect]

By taking such measures, the following effects are achieved. That is, since the address information for each font is written in the RAM when the device is initialized such as when the power is turned on, the bit data only needs to be written in the RAM for one type of font, and the RAM capacity is small.

〔Example〕

FIG. 1 is a block diagram showing the configuration of a printer in an embodiment of the present invention. In the figure, 1 is the main body of the device, and CP
U2 is provided. A ROM 4 storing operating programs and a RAM 5 for processing are connected to the CPU 2 via an address bus 3a and a data bus 3b. The RAM 5 has an area used as an address/information memory for storing address information and an area used as a bit data memory for storing bit data for printing out. Furthermore, CPU 2 and address converter 6. CG ROM7, operation panel 8
．． Parallel interface control section 9. Serial interface control unit 10. Interfaces 11 are connected via an address bus 3a and a data bus 3b, respectively. The address converter 6 converts the address output by the CPU 2 into a predetermined address as necessary. C.G.R.
OM7 is a ROM that stores bit data of each character and is used as a character generator. The operation panel 8 is an operation section through which an operator issues operation instructions to the CPU 2. A host personal computer 20 is connected to either of the parallel interface control section 9 and the serial interface control section 10, and provides an interface between the present apparatus and the host personal computer 20. The interface 11 serves as an interface between the CPU 2 and the printing device 12 . Note that 3C is a control signal, and 13 is a power supply.

In addition, the CPU 2 reads bit data designated by address information stored in an area used as an address information memory in the RAM 5 from the CG ROM 7 in response to the input data 10 inputted from the outside, and stores the bit data in the bit data memory in the RAM 5. a bit data writing means for writing into an area used as a bit data memory; and a printing unit for reading bit data corresponding to externally input character data from an area used as a bit data memory in the RAM 5 and outputting it as a printout using a printing device 12. and an output means.

FIG. 2(a) is a diagram showing the configuration of the RAM memory of the above device, and FIG. 2(b) is a diagram showing the configuration of the address information register in FIG. 2(a). As shown in FIG. 2(a), R
AM5 includes a working register 21 for CPtJ2 to perform arithmetic processing, an address information register 22 for storing fast font ID, and a bit map area 23 used as a bit data memory to write bit data read from CG ROM7. and a reception buffer 24 that temporarily holds information from the host personal computer 14. The address information register 22 has a configuration as shown in FIG. 2(b). 22a
is a font ID register that stores font ■D set for each character font. 22b is CG RO
Bit data stored in M7, i.e. area 22
This is a start address register for storing the start address of bit data having the font ID stored in a. 22C is a final address register for storing the final address of the bit data stored in the CG ROM 7, that is, the bit data having the font ID stored in the area 22a. 22d is C
This is an address byte number register for storing the amount of bit data stored in the G ROMT, that is, the bit data having the font 10 stored in the area 22a. These four registers indicate address information for characters of one type of font. Below, CG
Address information is stored in the same format as the number of font types stored in the ROM 7.

Next, the operation of this apparatus having the above configuration will be explained using the flowcharts shown in FIGS. 3(a) and 4.

First, using FIG. 3<8)(b), the flow of processing for creating address information of bit data in the CG ROMY and writing it into the RAM 5 at the time of initializing the device such as when the power is turned on will be explained.

First, in step 3a, the contents of the address (ADD) and counter (CNT) are initialized to zero.

Next, in step 3b, it is determined whether or not the font ID is stored at address D in the CG ROM 7. If the font ID is not stored at the ADD address, ADD is set to ΔDD+1 in step 3C, and it is determined whether ADD has reached the maximum address of the CG ROM 7 in step 3d. Here ADD is CG
If the maximum address of ROM7 has been reached, CGRO
Since the search for M7 has been completed, the process ends.

Further, if ADD has not reached the maximum address of the CG ROM 7, the processing from step 3b onwards is repeated. In this way, the addresses of the CG ROM 7 are sequentially searched, and if an address storing a font ID is found, then in step 3e, the font ID stored at that address is stored in the font 10 register 22a.

Since the address next to the stored address of the font 10 is the start address, ADD+1 is stored in the start address register 22b at step 3ft. Next, in step 3Q, ADD is set to ADD+1, and in step 3h, it is determined whether the ADD address is the final address where bit data of a character of one type of font is stored.

If the ADD address is not the final address, CNTeCNT+1 is set in step 31, and the processing from step 3g onwards is repeated. In this way, the CGROM 7 is searched until the final address is found, and when the final address is found, the ADD which was the final address is searched in step 3j.
Store the address in the final address register 22C. Next, CNT, which counts the number of addresses from the first address to the last address, is stored in the address byte number register 22d. Then, in step 32, CNT is set to 0, and the processes from step 3b onwards are repeated.

Next, using FIG. 4, host personal computer 1
The process of printing out according to the instructions from 4 will be explained.

If the font ID is input from the personal computer 14 in step 4a, step 4
Address information corresponding to the font ID input in step b is searched from the RAM 5. Then, in step 4C, bit data of the corresponding font ID is read from the CG ROM 7 according to this address information, and in step 4d, this bit data is written into the bit map area 23 of the RAM 5.

Here, when character data is input from the host personal computer 14 in step 4e, step 4
Edit one line of printout character data with f, and proceed to step 4.
In Q, printout is performed using printing bag @12.

As described above, according to this embodiment, bit data only needs to be written to the RAM 5 for one type of font, and the RAM capacity can be small.

Note that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

〔Effect of the invention〕

According to the present invention, when the device is initialized such as when the power is turned on, the font ID of the bit data in the CG ROM is
, start address, R end address, etc., write this address information to RAM, and when printing out, CG R is written according to this address information.
Since character data is read from OM and written to RAM, all character data is written to RAM and does not occupy a large area of RAM.
It is possible to provide a printer that can efficiently use M capacity.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention.
7. ) A diagram showing the memory configuration of the RAM, and a diagram showing the flow of processing for printing out according to instructions from the third sonal computer. 1... Device body, 2... CPU, 3a... address bus, 3b... data bus, 3C... control signal,
4...ROM, 5...RAM, 6...address converter, 7...CG ROM, 8...operation panel,
9... Parallel interface control unit, 10... Serial interface control unit, 11... Interface, 12... Printing device, 13... Power supply, 14...
Host personal computer, 21... Working register, 22... Address information register, 23...
・Bitmap area, 24... Receive buffer, 22
a...Font ID register, 22b...Start address register, 22C...Final address register, 2
2d: Address byte number register.゛Applicant's representative Patent attorney Takehiko Suzue Figure 3 (a) Figure 2 (a); Figure 2 (b) Figure 3 (b) Figure 4

Claims (1)

[Claims] In a printer that reads bit data corresponding to externally input character data from a character generator, once writes it into RAM, and then prints it out, the font ID and the corresponding font stored in the character generator are used for each font type. An address information memory that stores address information consisting of a start address and an end address of bit data, a bit data memory that stores bit data for printing out, and an address information memory that stores address information that stores bit data that is to be printed out, and the address information memory that stores address information that is composed of a start address and an end address of bit data. bit data writing means for reading designated bit data of address information stored in the character generator from the character generator and writing it into the bit data memory; and reading bit data corresponding to externally input character data from the bit data memory. A printer characterized by comprising a print output means for outputting a printout.