JPH08314700A - Control system - Google Patents

Abstract

PURPOSE: To provide the control system which easily alters the operation of an electric equipment by modifying a software program. CONSTITUTION: A CPU 2 which controls the operation of the electric equipment 11 is connected to flash memories 6 and 7 for storing the program code through a data bus 3 and an address bus 4 and also connected to a communication device 5 connected to an external device by a communication line 12; and the program code sent from the external device by the communication device 5 is written in the flash memory 6 or 7 and the start address of a start address storage area is changed to make the CPU 2 operate according to a new program, thereby easily altering its operation without disassembling the electronic equipment 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system for controlling electric equipment using a microprocessor.

[0002]

2. Description of the Related Art In recent years, a mainstream is one in which a microprocessor is built in a device to control an electric device by a software program. By programming with software, there is an advantage that the operation of the electric device can be easily changed without changing with hardware.

This is because the microprocessor controls the peripheral elements according to the software program stored in the storage device (memory), and the operation of the microprocessor can be changed only by replacing this memory.

[0004]

The software can be changed only by replacing the memory. However, since the memory element itself is mounted inside the electric device, the cover of the electric device is opened to replace the memory device. There must be.

For this reason, even in the case of a simple software change, it is necessary to disassemble the electric equipment, replace the memory, and then reassemble it. This is troublesome, and there is a problem in that reliability is ensured when the electric device is disassembled and then assembled. In particular, in medical electrical equipment and the like, medical safety tests such as withstand voltage and leakage current must be performed again, which is a problem in terms of maintenance.

Further, since a socket for an element is used to enable replacement of the memory, there are drawbacks that the mounting area becomes large and the cost is increased due to the socket.

The present invention has been made in view of these problems, and an object of the present invention is to provide a control system capable of easily changing the operation of an electric device by changing a software program.

[0008]

The present invention comprises a rewritable flash memory for storing a program code indicating a working procedure of a microprocessor, and an interface for receiving data from the outside of an electric device. The flash memory is divided into a plurality of areas, and a plurality of types of program codes can be stored in each area, and one of these program codes is selectively executed.

When a change occurs in the program, this program or a specially-provided program receives a new program code from the outside of the electric device by communication or directly from the bus, and the remaining 1 area of the flash memory is read. Write in one. When the writing is completed, the program can be changed by passing control of the microprocessor to the program code in the written area.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 relate to a first embodiment of the present invention, FIG. 1 shows a configuration of a control system of the first embodiment, and FIG. 2 shows a configuration of a control system of a modified example of the first embodiment. 3 shows the structure of the memory map, FIG. 4 shows the processing contents when the operation of the microprocessor is started, FIG. 5 shows the processing contents for rewriting or changing the program code, and FIG.
The operation | movement explanatory drawing of is shown.

The control system 1 according to the first embodiment of the present invention shown in FIG. 1 is capable of rewriting using communication. In this control system 1, a microprocessor (hereinafter, referred to as "control system") for controlling the entire control system is used. , Abbreviated as CPU) 2 is a communication device (or communication element) 5 via a data bus 3 and an address bus 4, flash memories 6 and 7 as rewritable storage elements used for storing program codes, and data. And the RAM 8 for stacking.

These devices (that is, the communication device 5, the flash memories 6 and 7, and the RAM 8) are CPs.
It is controlled by a read / write signal from U2 and a control signal 10 generated by a decoder 9 from an address signal.

Further, at least a part of the electric device 11 whose whole or at least a part of its operation is electrically controlled by the CPU 2 is connected to the CPU 2 through the data bus 3 and the address bus 4, and Decoder 9
The CPU 2 can be controlled by the control signal 10 via.

That is, the electric device 11 has a structure in which its operation is controlled by the CPU 2 and a different operation or change of the operation can be performed by changing the program of the CPU 2.

The communication device 5 functions as an interface connected to an external device such as a personal computer outside the control system 1 via, for example, a serial communication line 12, and has at least a function of receiving program code data from the external device. .

The control system 1'of FIG. 2 shows a modification in which the data of the program code can be directly received from an external device via the data bus 3 and the address bus 4. Similar to FIG. 1, the CPU 2 is connected with the communication device 5, the program code storage flash memories 6 and 7 via the data bus 3 and the address bus 4, and the RAM 8 for stacking data and the electric device 11. ing.

These devices and electric equipment 11 are controlled by control signals via the decoder 9. Also,
In this modification, the bus controller 13 controls input / output of data from an external device. FIG. 3 shows the structure of the memory maps of the control systems 1 and 1 '.

The memory is roughly divided as shown in FIG.
Alternatively, a RAM area formed by the RAM 8 of FIG.
It is divided into a ROM area formed by the flash memories 6 and 7. The RAM area is an area for storing data during execution of the program and a stack, and the ROM area is the CPU 2
The program code which is the operation procedure of is stored.

As shown in FIG. 3, the ROM area includes a start-up routine area 21 starting from address 0 (or 0 address), a start address storing area 22 and a plurality of code areas, that is, a first code area 23a and a second code area 23b. Become.

In FIG. 2, the start address of the second code area 23b is set following the end address of the first code area 23a, and the start of the data stack area 24 of the RAM area is provided following the end address of the second code area 23b. The address is set. For example, in the flash memory 6, the startup routine area 21, the start address storage area 22 and the first code area 23a
And the second code area 2 is formed in the flash memory 7.
3b is formed.

When the start address stored in the start address storage area 22 is the start address of the first code area 23a, the program code of the first code area 23a is executed and stored in the start address storage area 22. When the start address is the start address of the second code area 23b, the program code of the second code area 23b is executed.

FIG. 4 shows a schematic processing procedure when the operation of the CPU 2 is started. When the power is turned on, the CPU 2 first executes the step S
The startup routine 21 of No. 1 is executed. That is,
The start-up routine 21 at the address 0 is executed, and then the memory and register in step S2 are initialized.

Subsequently, the stored contents of the program start address storage area 22 in step S3, that is, the start address is referred to, and the program code indicated by the start address is executed. Depending on the value of the start address at this time, the first code area 23a in step S4a, or step S4a
One of the programs stored in the second code area 23b of 4b is executed.

Therefore, for example, the start address storage area 2
In FIG. 2, the start address value of the first code area 23a is first written to the start address value of the second code area 23b so that the program in the second code area 23b can be executed. ing.

The flowchart of FIG. 5 shows the processing procedure for changing the program code, and FIG. 6 shows an explanatory view of its assistance. As shown in FIG. 6A, the start address storage area 22 has a start address ΔΔ of the first code area 23a.
Assuming that ΔΔ is stored, the first code area 23a in step S11 is set at the program start time in FIG.
Program (referred to as a first program) is executed. In this case, the data in the data stack area (its start address is indicated by □□□□ in FIG. 6A) is referred to according to the program contents.

FIG. 6A shows a program counter indicating the execution position of the first program, which execution position is in the first code area 23a. In addition, in FIG. 6, the first
The diagonal lines of the code area 23a and the second code area 23b indicate that the program code is written, and the entire second code area 23b of FIG. 6A and FIG.
A part of the blank in the second code area 23b in (B) shows a state where no program code is written. Further, for simplification, the reference numerals 21 to 23b are shown only in FIG. 6A and are omitted in FIGS. 6B to 6G.

When an external command is sent from an external device during execution of the first program, the communication device 5 in FIG. 1 notifies the CPU 2 of the external command by an interrupt or the like. Further, in the case of FIG. 2, when an external command is sent from an external device, the external command is transmitted to the CPU 2 by an interrupt or the like via the bus controller 13.

In step S12, the CPU 2 determines whether or not the external instruction is a program change instruction, and if it is not the program change, the step S1 is continued. In the case of a program change instruction, the CPU 2 receives a new program code (referred to as a second program code) from the communication / bus as in step S13, and performs the flash memory writing process in step S14.

That is, in the case of the configuration of FIG. 1, the data of the second program code transmitted from the external device is received via the communication device 5, and is stored in, for example, the second code area 23b of the flash memory 7 on the lower side. Data is sequentially written from the address (the first program code is written in the flash memory 6).

In the case of the configuration of FIG. 2, the bus controller 13 receives the data of the second program code sent via the data bus 3 and the address bus 4, and the CPU
2 sequentially writes the received data of the second program code into, for example, the second code area 23b of the flash memory 7 from the lower address.

FIG. 6B shows a state in the middle of writing in the second code area 23b. Then, in step S15 of FIG. 5, it is determined whether or not the writing is completed. If the writing is not completed, the process returns to step S13 to continue the receiving and writing processes until the writing is completed. FIG. 6C shows a state in which the writing of the data of the second program code is completed in the second code area 23b.

After this writing is completed, step S16
The program code start address is rewritten. C
As shown in FIG. 6D, the PU 2 rewrites the contents of the start address storage area 22 to XXX which is the start address of the second code area 23b.

After the completion of this rewriting, as shown in step S17, it is reset or the power is turned on again. That is, by resetting the control system 1 or 1'or turning on the power again, the current program operation is reset and the program operation is performed from the beginning.

By this reset or turning on the power again, the start position of the program counter returns to 0, and the start-up routine of step S18 is executed. Figure 6
(E) shows that the start position of the program counter has returned to address 0. By executing this startup routine, the start address of step S19 is read.

That is, the CPU 2 executes the startup routine. By executing this start-up routine, the start address of the program code storage area 22 is referenced (FIG. 6F shows the state where the start address is referenced).
Since the start address XXXX of the code area 23b is written, the second program stored in the second code area 23b is executed.

That is, the new program starts in step S20. FIG. 6G shows a state in which the second program stored in the second code area 23b is being executed. In this way, the program of the control system is rewritten from the first program to the second program, and the operation of the electric device 11 is controlled according to the rewritten new program.

In FIG. 5, after the start of the new program in step S20, the process returns to step S11. In this case, the program execution in the first code area in step S11 becomes the program execution in the second code area, and the program execution in the second code area can be further changed by an external instruction. To make this change, a new program is written or rewritten in the first code area 23a. Then, after writing all, the start address is rewritten, and a new program can be executed by resetting or turning on the power again.

According to this first embodiment, the control system 1
Alternatively, the communication device 5 or the bus controller 13 as a means for receiving a new program code from the outside of 1 ', the flash memory 6 or 7 as a program changing storage device for storing the received new program code, and the new program code. Since the start address storage area 22 indicating the start address of the electric equipment 11 is provided, the program can be run with a new program code without opening the cover of the electric device 11 or the control system 1, 1'and replacing the memory. Therefore, the labor of disassembly and assembly can be saved.

Further, it is unnecessary or possible to minimize the test concerning the safety of the electric device 11 after the disassembly. In addition, the program can be easily changed, and the operation of the electric device 11 can be easily changed by this change. Furthermore, the possibility of incorrect assembly after disassembly is eliminated, and the electrical device 11
Since the operation of can be changed, reliability and maintainability can be improved.

Next, a second embodiment of the present invention will be described. Figure 7
9 to 20 relate to the second embodiment of the present invention, FIG. 7 shows the configuration of the control system 29 of the second embodiment, FIG. 8 shows the configuration of the memory map, and FIG. 9 shows a flow chart for changing the program code. .

The control system 29 of the second embodiment shown in FIG.
Has a communication device 5 and a bus controller 13 so that the program code can be changed from an external device through either communication or bus.

Further, in the first embodiment, the ROM area was formed by the two flash memories 6 and 7, but in this embodiment, the ROM area has four ROMs (that is, the 0th ROM).
30, first ROM 31, second ROM 32, third ROM 3
3). Then, as shown in FIG.
The ROM 30 stores a startup routine and a program code rewriting program.

Further, the first ROM 31 to the third ROM 33
Different main program codes (first to third main program codes) can be written in each. Further, as shown in FIG. 8, the first ROM 31 to the third RO
The same address is set in M33.

Then, as shown in FIG. 7, each chip select terminal CE is connected to a dip switch 36 pulled up by a resistor R, and one of the three switches DS1 to DS3 of the dip switch 36 is selected.
You can access two ROMs, run the program code written in the selected ROM,
The program code can be rewritten.

The plurality of 0th ROM 30 to 3rd ROM
Reference numeral 33 is a flash memory. That is, as shown in FIG. 8, these three first ROM 31 to third RO
M33 is connected in parallel to the same address, and only one is selected by the dip switch 36 (since the switch DS1 is 0 in FIG. 7, the first ROM 31 is selected).

The DIP switch 36 is installed at a position such as a rear panel of the control system 29 that can be operated from the outside, and a plurality of program codes can be switched and executed as necessary by an operation from the outside.

FIG. 9 shows a flowchart for changing the program code or rewriting the program. When the program starts, the CPU 2 executes the normal program in step S21.

Since the first ROM 31 is selected by the dip switch 36 in the setting of FIG. 7, the CPU 2 is executing the first main program in the code area of the first ROM 31 of FIG.

Then, in step S22, it is determined whether or not the program is changed, and when the program code change instruction is received by the external instruction, the CPU 2 executes the rewriting program in step S23. That is, the execution position of the program counter is set to the start address (0200H) of the rewriting program shown in FIG.

Then, as shown in step S24, the new program code is received from the communication or the bus, and the flash memory rewriting process shown in step S25 is performed.
Before performing the flash memory rewriting process shown in step S25, the DIP switch 36 is operated to operate the switch DS2.
Is set to 0 or DS3 is set to 0 to specify the ROM to be written.

In the next step S26, it is determined whether or not the rewriting has been completed. If the rewriting is not completed, the process returns to step S24, and the process of communication or receiving a new program code from the bus and rewriting the flash memory is performed.

After the rewriting is completed, step S2
C by performing the process of 7 reset or power-on
PU2 executes the new program after rewriting in step S21.
It is executed as a normal program shown in.

By this rewriting, for example, the second ROM 3
2 by writing a new program into the third ROM 33 by an external command during execution of this normal program, and by resetting or turning on the power again, the three switches DS1 to DS3 are set to 0, thereby a plurality of programs are written. Any program can be executed.

According to the second embodiment, it is possible to execute any one of the plurality of programs by selecting a plurality of switches. Further, it is possible to deal with the case where the addresses are the same or some of the addresses overlap. Also, the program code can be received from an external device by using either communication or a bus. Others have substantially the same effects as the first embodiment.

In the description of each of the above embodiments, RA
It is assumed that the M8 data stack will be used in common, but by dividing the RAM into multiple areas,
The data may be changed or rewritten according to the program to be executed.

[Additional Notes] 2. 2. The control system according to claim 1, wherein the storage element has an area for storing two or more different program codes and an area for storing one start address.

3. The control system according to appendix 2, comprising means for switching and executing the two or more different program codes.

4. 2. The control system according to claim 1, wherein the means for receiving the program code from the outside is a bus that is communicated or output to the outside.

5. The storage element for storing a rewrite program code of one storage element, and the plurality of rewritable storage elements storing a program code according to claim 1.
A control system comprising: means for selecting one of the plurality of storage elements, and means for executing the one storage element or rewriting according to the storage element rewriting program.

[0060]

As described above, according to the present invention, in a control system for controlling an electric device by using a microprocessor, a means for receiving data of a program code from the outside of the electric device and storing the program code. Since the rewritable storage element and the means for indicating the start address of the program code stored in the storage element are provided, the program code can be rewritten without disassembling the electric device. It is possible to save the labor required for assembling, and to omit the safety test due to the disassembly and the like, and it is possible to easily change the operation of the electric device.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a control system according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a control system of a modified example of the first embodiment.

FIG. 3 is a diagram showing a memory map.

FIG. 4 is a flowchart showing processing of a startup routine.

FIG. 5 is a flowchart showing a processing procedure for changing a program code according to the first embodiment.

FIG. 6 is an explanatory diagram of assistance of FIG.

FIG. 7 is a schematic configuration diagram of a control system according to a second embodiment of the present invention.

FIG. 8 is a diagram showing a memory map.

FIG. 9 is a flowchart showing a processing procedure for changing a program code according to the second embodiment.

[Explanation of symbols]

 1, 1 '... Control system 2 ... CPU 3 ... Data bus 4 ... Address bus 5 ... Communication device 6, 7 ... Flash memory 8 ... RAM 9 ... Decoder 10 ... Control signal 11 ... Electrical equipment 12 ... Communication line 13 ... Bus Controller 21 ... Startup routine area 22 ... Start address storage area 23a ... First code area 23b ... Second code area 24 ... Data stack area

Claims (1)

[Claims] 1. A control system for controlling an electric device using a microprocessor, means for receiving data of a program code from the outside of the electric device, a rewritable storage element for storing the program code, and the storage device. A control system comprising: means for indicating a start address of the program code stored in, and operating according to the program code and the start address.