JP2597156Y2 - Evaluation microcomputer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an evaluation microcomputer for developing a microcomputer program for mass production.

[0002]

2. Description of the Related Art Generally, a one-chip microcomputer for mass production has a built-in ROM for controlling the operation of the microcomputer itself, but this ROM is often made of a mask. That is, the program data written in the ROM cannot be rewritten, and when writing the program data to the ROM, sufficient care must be taken so that incorrect program data is not written.

Therefore, an evaluation microcomputer having almost the same function as a mass-production one-chip microcomputer is used today so that correct program data can be written in a ROM, and this evaluation microcomputer controls its own operation. A program memory for control is provided externally, and this program memory is configured as a program RAM that operates as a ROM but can write and read program data. This program RAM has a ROM desired by the user from outside.
Is written in the memory, and the evaluation microcomputer operates based on the program data read from the program RAM. Process data obtained by the evaluation microcomputer operating based on the program data from the program RAM is written to the data RAM inside the evaluation microcomputer. Then, the evaluation microcomputer is set at a predetermined timing (address of the data RAM to be evaluated).
In the state where the break occurs, the processing data written in the data RAM is read out and compared with the data to be originally obtained, thereby determining whether the processing data is correct or not, that is, whether the program data is correct or not. By repeating the above evaluation operation, correct program data to be mask-processed is obtained in the ROM inside the one-chip microcomputer for mass production.

Here, in a one-chip microcomputer for mass production, in order to reduce the chip size,
Registers and the like that do not need to read once written data to the internal bus are configured for writing only, and realize a smaller or higher-density chip by omitting a read wiring pattern to the internal bus. The write-only register is provided and connected for each input / output port, for example, and is used when these input / output ports are set in a programmable manner such as open drain, pull-up, pull-down, and CMOS output. In other words, if the programmer sets predetermined control data in a certain register and sets the I / O port to a certain form once, the contents of this register will not be read out to the internal bus and used thereafter, so this register will be written. Dedicated and good.

As described above, since the evaluation microcomputer has substantially the same function as the mass-production one-chip microcomputer, it naturally has the write-only register of the mass-production one-chip microcomputer. When the program evaluation is performed, the content written in the write-only register of the evaluation microcomputer is held without being read.

[0006]

However, with the sophistication of mass-produced one-chip microcomputers, the number of input / output ports to be set in a predetermined form, for example, tends to increase. When a program evaluation is performed using an evaluation microcomputer having substantially the same function as such a high-performance mass-production one-chip microcomputer, checking the form of the input / output port has had to rely on the memory of the programmer until now. I didn't get it. However, with the increase in the number of I / O ports, the programmer cannot remember the configuration of all I / O ports, and in addition, as described above, the contents of each write-only register for determining the configuration of each I / O port Cannot be read, it is uncertain that the form of each input / output port is checked. Therefore, there is a problem that it is impossible for an external host computer or the like to judge whether data at each input / output port of the evaluation microcomputer is correct or incorrect, that is, there is a problem that a correct program evaluation cannot be performed.

Accordingly, an object of the present invention is to provide an evaluation microcomputer which can read out and confirm the same contents as the contents written in the write-only register.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the feature of the present invention is that control data for setting a predetermined function to a predetermined form is stored in an internal bus. An evaluation microcomputer having substantially the same function as a mass-production microcomputer including a write-only register that does not read out the written control data to the internal bus and that does not read out the written control data, Registers and
A write / read register corresponding to the register, and when the write / read control signal instructs the writing of the control data, simultaneously write the control data to the register and the write / read register via the internal bus; When the write / read control signal instructs the reading of the control data, the control data is taken out only from the write / read register via the internal bus and the contents of the register can be confirmed. .

[0009]

According to the present invention, the control data is simultaneously written into the register corresponding to the write-only register of the mass-production microcomputer, and the control data is written into the evaluation microcomputer. Since a read / write register that can be read is provided on the internal bus, the contents of the write-only register can be checked, and correct program evaluation can be performed.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be specifically described with reference to the drawings. FIG. 1 is a block diagram for explaining the evaluation microcomputer of the present invention. In FIG. 1, (1)
Is an evaluation microcomputer having substantially the same function as a mass-production microcomputer. Here, the mass-production microcomputer writes control data via a register in which control data for determining the form of an input / output port or the like is stored, that is, the internal bus, but writes the control data to the internal bus. A write-only register that cannot be read is built in, and a write-only register (2) is provided inside the evaluation microcomputer (1) according to this. Further, inside the evaluation microcomputer (1), (3) is a write / read register capable of writing control data via the internal bus (4) and reading control data onto the internal bus (4). , A write / read control signal is applied together with the write only register (2). That is, the write / read control signal for setting the write state is applied to both registers.
When applied to (2) and (3), control data obtained from a development support board, which will be described later, is simultaneously written into both registers (2) and (3) via the internal bus (4). The bit output of the write-only register (2) is connected to the gate of the transistor constituting the input / output port, and the input / output port is set to a predetermined form by the bit output of the write-only register (2). Become. Conversely, the write / read control signal for setting the read state is
(2) When applied to (3), write-only register (2)
Is not connected to the internal bus (2), only the write / read register (3) is in a read state to the internal bus (4) and is taken out to the outside via the internal bus (4). . The reason why the write / read register (3) is newly provided without using the write-only register (2) as the write / read register is that the evaluation microcomputer (1) has the same pattern on the chip as the mass production microcomputer. Therefore, changing the pattern of the write-only register (2) so that it can be used for both reading and reading also forces a change of the pattern around the register. As a result, the evaluation microcomputer is used.
This is because the large-scale pattern change of (1) is required. On the other hand, when the write / read register (3) corresponding to the write-only register (2) is simply provided on the chip, the pattern change is reduced, and the evaluation microcomputer (1) can be developed quickly. (5) is a data RAM for writing or reading processing data of the evaluation microcomputer (1).

(6) is the development support board described above. On the development support board (6), (7) is the program RAM
And program data for operating the evaluation microcomputer (1) and a write-only register (2).
Program data for writing predetermined control data and the like are stored in the write / read only register (3). These program data are stored in the internal bus
(8) It is taken into the evaluation microcomputer (1) via (4). (9) is an evaluation RAM
And command data for causing the evaluation microcomputer (1) to perform an evaluation operation, that is, a break or a one-step operation, is stored.

Reference numeral (10) denotes a host computer capable of confirming the written contents of the data RAM (5) in the evaluation microcomputer (1) and the contents of other various registers. Furthermore, the host computer (10) has an FD
An external storage medium (not shown), such as a floppy disk, can be mounted. The program RAM (7) on the development support board (6) contains program data stored in advance in the external storage medium. The program data is loaded via the bus (8) and required program data is written at a predetermined address.

In the above configuration, when the evaluation microcomputer (1) is operated for evaluation, the contents written in the write / read register (3) of the evaluation microcomputer (1) are transferred via the internal bus (4). By taking it out to the outside, the same contents to be written to the write-only register of the mass-production microcomputer can be confirmed by the host computer (10). However, the correct setting of the data at the input / output port can be reliably checked based on the contents of the read / write register (3) easily read without relying on the memory of the programmer for the programmable setting state of the input / output port. In other words, program evaluation can be performed reliably.

[0014]

According to the present invention, the control data is simultaneously written into the write-only register of the mass-production microcomputer in the evaluation microcomputer, and the control data is written to the internal bus. Since a write / read register capable of reading data is provided, the contents of the write-only register can be checked, and an advantage that correct program evaluation can be performed can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining an evaluation microcomputer of the present invention.

[Explanation of symbols]

 (1) Evaluation microcomputer (2) Write-only register (3) Write-read register (4) Internal bus

Claims (1)

(57) [Scope of request for utility model registration] 1. A mass-production microcontroller for writing control data for setting a predetermined function to a predetermined form via an internal bus, and including a write-only register that does not read the written control data to the internal bus. An evaluation microcomputer having substantially the same function as a computer, wherein the evaluation microcomputer corresponds to the write-only register and
And a write / read register corresponding to the register, and the register and the write / read register
When a simultaneously and commonly applied write / read control signal indicates writing of the control data, the control data is simultaneously written to the register and the write / read register via the internal bus, and the write / read control signal is An evaluation microcomputer which, when instructing the reading of the control data, takes out the control data only from the write / read register via the internal bus to the outside so that the contents of the register can be confirmed. .