JP2003067212A - Memory rewriting control system and memory rewriting method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a memory rewriting control system and the control method capable of notifying the outside about the completion of rewriting even not provided with an exclusive region for holding and saving a communication program in a device wherein a communication program used in a communication with a data transmitting party is installed in a ROM to be rewritten and only a rewriting program is installed in other ROM. SOLUTION: In a device wherein a communication program used in a communicating with a data transmitting party is installed in the ROM to be rewritten and only a rewriting program is installed in other ROM, completion of rewriting is notified to the data transferring party by starting to operate an interface communication line connected to the data transferring party after completing the rewriting, while the transferring party performs recovery of a communication by recognizing that rewriting to the ROM is completed when the above operation by a signal is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a rewritable non-volatile memory (flash ROM or the like) equipped with firmware, receives the contents of the ROM by communication, and rewrites the received contents to upgrade the version. The present invention relates to a memory rewriting control system for a device that performs the above and a control method thereof.

[0002]

2. Description of the Related Art Conventionally, in a device using a ROM which is a rewritable non-volatile memory, when the ROM is rewritten to update the firmware, the following methods (1), (2) and (3) are used. Then, the firmware version is being updated.

(1) A communication program for communicating with a data transfer source and a ROM rewriting program are installed in a memory other than the ROM to be rewritten, the communication program is executed, data is received from the transfer source, RO above
Change the contents of M.

(2) The communication program for communicating with the data transfer source and the ROM rewriting program are installed in the ROM itself to be rewritten, and when rewriting the ROM, the communication program is executed to execute the ROM rewriting program.
Transfers to a memory other than ROM, executes it, receives data from the outside, and changes the contents of ROM.

(3) A communication program for communicating with the data transfer source is mounted on the ROM itself to be rewritten, and R
Only the OM rewrite control program is installed in another memory. When rewriting the ROM, the communication program installed in the ROM to be rewritten is executed to
After receiving the M data, the ROM rewrite control program is executed to change the ROM contents.

In the above-mentioned conventional examples (1) and (2), since a dedicated memory area having a relatively large capacity is required to install a program for communication, the above-mentioned conventional example (3) should be executed. Saves hardware resources.

[0007]

However, in the above-mentioned conventional example (3), when the transfer is completed and the rewriting of the ROM is started, it is impossible to communicate with the data transfer source. Therefore, there is a problem that it is not possible to notify the outside that the rewriting is completed.

In this case, if the user turns off the power during rewriting, the contents of the ROM are damaged and cannot be restored. Therefore, it is necessary to notify the end of rewriting to the outside by some method.

According to the present invention, a communication program for communicating with a data transfer source is installed in a rewriting target ROM, and only a rewriting program is installed in another ROM, and the communication program is held or saved. It is an object of the present invention to provide a memory rewrite control system and a control method therefor that can notify the end of rewriting to the outside without having a dedicated area.

[0010]

According to the present invention, in a device in which a communication program with a data transfer source is installed in a rewriting target ROM and only a rewriting program is installed in another ROM, after rewriting, By activating the interface communication line connected to the data transfer source, the data transfer source is notified of the end of rewriting, and when the transfer source detects the signal operation, the ROM rewriting is regarded as completed. It is a device for restoring the

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 is a block diagram of an apparatus equipped with a memory rewriting control system CS1 according to a first embodiment of the present invention.

The memory rewrite control system CS1 has a board 10 having a ROM 12 for rewriting, and a main body device 20 for transferring rewriting data to the board 10.

That is, the memory rewrite control system CS1
Is a board 10 that updates the firmware, a main body device 20 that transfers the update program to the board 10,
A personal computer 30 equipped with software for the user to control the firmware update.

The board 10 is a C for controlling the operation of the board.
PU11, ROM12, flash ROM13,
It has a RAM 14 and an interface unit 15.

Both the ROM 12 and the flash ROM 13 store programs for operating the CPU 11. The flash ROM 13 is rewritable.

The RAM 14 includes a ROM 12 and a flash R.
This is a memory area in which the CPU 11 executes the programs stored in the OM 13.

The interface unit 15 is an interface unit for communicating with the main body device 20, and in the above embodiment, it uses the IEEE1284 interface to transfer commands and data.

FIG. 2 shows the main unit 20 in the above embodiment.
IEEE1 used for communication between the board and the board 10
It is a figure which shows an example of the signal line operation | movement of 284 interface.

Here, the main unit 20 is an IEEE128
4 operates as a host, and the board 10 side operates as a peripheral in the ECP mode. This basic operation is I
Since the standard is EEE1284, its description is omitted, but the signal operation of the part executed in the above-described embodiment is the following operation.

First, the initialization (COMPABLE) will be described.

Starting from a state where they are reset to each other, negotiation is performed from the main body device 20, and the board 10 responds to this, whereby communication can be performed in the bidirectional mode. In the reset state, the Select signal output by the board 10 becomes Low, and changes to High when the negotiation from the main body device 20 comes. This High state does not become Low as long as communication is continued in the ECP mode.

Next, communication (ECP Forward) from the main unit 20 to the board 10 will be described.

When the negotiation is completed, normally,
The communication mode from the main body device 20 to the board 10 is set, and the data from the main body device 20 can be transferred to the board 10.

Next, communication (ECP reverse) from the board 10 to the main body device 20 will be described.

The data from the board 10 is transferred to the main unit 20.
Board 10, the board 10 sends the nFault signal to
It is changed to Low and a direction change request to the main body device 20 is issued.

On the main unit 20 side, nFault is Lo
When it detects that it has become w, it changes nInit to Low, switches the communication direction, and the board 10
A change in t is detected and data transfer is started. When the transfer is completed, the board 10 returns nFault to High, the main unit 20 detects that nFault has been returned to High, and returns nInit to High, and the communication direction is changed from the main unit 20 to that of the board 10. Turn it back. Thereafter, when there is no data to communicate with each other, the signal is stopped in the Forward Idle state of the event 33 in FIG.

After the data transfer is completed, Forward
The flash ROM 13 of the board 10 is rewritten while the d Idle state is held, and the Select signal is once set to Low by the initialization of the board 10, thereby indicating to the main body device 20 that the ROM rewriting is completed.

FIG. 3 shows the board 10 in the above embodiment.
It is a figure which shows an example of the communication sequence between the main body apparatus 20 and the board 10 when upgrading the firmware of.

First, the flash ROM 13 of the board 10
Then, the data to be written this time is transferred from the PC 30 to the main body device 20, and the main body device 20 temporarily stores the received data in the RAM 24.

Next, the main body device 20 communicates with the board 10 through the IEEE1284, and sends a download start request command. On the board 10 side, if there is work in progress, etc., the confirmation of download NG is confirmed by the main unit 20.
Return to and if there is no work in progress, download is OK
Is returned to the main body device 20.

FIG. 4 is a diagram showing a memory map of the flash ROM 13 in the above embodiment.

FIG. 5 shows the board 10 in the above embodiment.
5 is a flowchart showing a download control operation in FIG.

FIG. 6 is a flowchart showing the download control operation in the main body device 20 having the same operation.

Here, as shown in FIG. 4, the control of these commands and responses, the driver of IEEE1284, etc. are stored in the ROM 13. In ROM12,
A boot program that is first activated at reset and a rewrite control program for the flash ROM 13 are stored. Other programs are stored in the ROM 13, that is, the programs that execute the functions of the board 10 including the communication program with the main body device 20 are stored in the ROM 13.

The operation viewed from the board 10 will be described below. The main body device 20 performs an operation corresponding to the board 10.

When the board 10 receives the download start request command from the main body device 20 (S1, S23) and the download is possible at that time, a response to the download start confirmation OK is returned to the main body device 20 (S3, S23).
24) The data transfer starts. The board 10 notifies the relative address of the data block to be transferred by the download notification command (S5, S27), and receives the data of the block corresponding to the received address together with the download response response from the main body device 20 (S6, S29). The received data is added with the checksum and stored in the RAM 14 (S8).

When the main device 20 has transferred all the data, finally, the data of data size = 0 is transferred (S3
0), the board 10 that has received this (S7) considers that the data reception has been completed, checks all the received data, and sends a download end notification command.
It is sent to the main body device 20 (S9, S31).

On the board 10, execution of all programs including the data transfer program is completed, that is, execution of all programs stored in the flash ROM 13 is completed (S9), and execution of the ROM rewriting program stored in the ROM 12 is completed. Is started (S10). After that, the communication program between the main body device 20 and the board 10 and the program stored in the flash ROM 13 of the board 10 cannot be used.

When the rewriting of the flash ROM 13 is completed successfully (S11), the board 10 is restarted and the initialization program stored in the rewritten flash ROM 13 is executed (S12). At this time, the IEEE1284 is also initialized and has been stopped in the Forward Idle state until then, but once it is reset, the Select signal changes to Low.

FIG. 7 is a diagram showing a memory map of the main body device 20.

In this example, as in the case of the board 10, another ROM 22 has a boot portion, but a portion other than the ROM 22 may have a boot portion.

In the main body device 20, after the download end notification command is received (S31), the communication of the board 10 is stopped (IEEE1284 is Forward
rdIdle state) and the main unit 2 of FIG.
As shown in the RAM 24 memory map of 0, the rewriting wait flag defined in the RAM area is turned on, and the RO of the board 10
Since M is being rewritten, the fact that the power is not turned off is displayed on the operation / display unit 26 (S32).

The rewriting wait flag is ON, and S
When detecting that the select signal has changed to Low (S33), the main body device 20 notifies the PC 30 of the end of the download process, assuming that the board 10 has completed the ROM rewriting, and at the same time, the operation / display unit 2
6 is returned to the normal standby state (S35). If the signal does not move even after waiting for a predetermined time (S34), it is considered that the rewriting is not normally completed, and an error signal is returned.

In the above embodiment, the main body device 20 starts to transfer the data to the board 10 after receiving all the data from the PC 30. However, if the RAM of the main body device 20 does not have enough space, an appropriate size is obtained. The block may be transferred to the board 10 each time it is received from the PC 30.

When the main unit 20 detects a signal line, C
The PU interrupt may be used, or the control program of the main body device 20 may periodically poll to detect the state.

According to the above embodiment, the end of ROM rewriting is judged by detecting the change in the signal line.
As a communication program required for communication between the main body device 20 and the board 10, the ROM rewriting is completed from the board 10 to the outside without storing a large program.
You can be sure to notify.

[Second Embodiment] In the second embodiment of the present invention, at the time when the board 10 detects that the Select signal is changed to Low, the main unit 20 once initializes communication and rewrites. Operate the subsequent communication program, R
This is an embodiment in which the result status etc. when the OM is written is returned by communication and the main body device 20 judges whether or not the main device 20 is normally completed by looking at the result status etc.

FIG. 9 is a flow chart showing the operation of the main body device 20 in the second embodiment.

FIG. 10 is a flow chart showing the operation of the board 10 in the second embodiment.

FIG. 11 is a diagram showing a memory map in the RAM 14 of the board 10 in the second embodiment.

As shown in FIG. 11, the board 10 sets the data rewriting flag indicating whether or not the data is being rewritten at present in the backed up area of the RAM 14 regardless of the power ON / OFF. Normally, the data rewriting flag is set to OFF.

After the data transfer from the main unit 20 is completed (S87, S60), the board 10 does not return the download end notification command, turns on the data rewriting flag, and enters the rewriting operation of the flash ROM 13 ( S89).

After rewriting (S90), flash ROM
The checksum of the internal data of 13 is calculated, the calculated value is held in the RAM 14, and then the boot program is activated (S91). By this start-up operation, as in the first embodiment, the main unit 20 is
After the change in the t signal is detected and the communication is restored, if the data rewriting flag is ON in the board 10 (if the data rewriting is started immediately after the data rewriting) (S92), the main unit 20
Checksum value stored in the flash ROM1
The status at the time of rewriting 3 is returned as a parameter of the download end notification command, and the data rewriting flag is turned off (S93).

After the communication is restored, the main body device 20 receives the download end notification (S74) and compares the checksum value with the checksum value at the time of data transfer (S7).
5) If this comparison result is different, terminate abnormally with PC
If the comparison result is the same, the normal end is notified to the PC 30, the operation / display unit 26 is returned to the normal state, and the download mode is ended (S7).
6).

By performing the control as described above, it is possible to more accurately check whether or not the ROM rewriting on the board 10 is normally completed.

[0056]

According to the present invention, by detecting a change in the signal line and issuing an end notification, it is possible to save a large program that communicates between the main body device and the board without having to separately carry it. There is an effect that the completion of memory rewriting is notified and processing such as power-off can be safely executed.

[Brief description of drawings]

FIG. 1 is a block diagram of an apparatus equipped with a memory rewrite control system CS1 according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of a signal line operation of an IEEE1284 interface used for communication between the main body device 20 and the board 10.

3 is a diagram showing an example of a communication sequence between the main body device 20 and the board 10 when upgrading the firmware of the board 10. FIG.

FIG. 4 is a diagram showing a memory map of a flash ROM 13.

5 is a flowchart showing a download control operation on the board 10. FIG.

FIG. 6 is a flowchart showing a download control operation in the main body device 20.

7 is a diagram showing a memory map of the main body device 20. FIG.

8 is a diagram showing a memory map in a RAM 24 of the main body device 20. FIG.

FIG. 9 is a flowchart showing an operation of the main body device 20 in the second embodiment.

FIG. 10 is a flowchart showing the operation of the board 10 in the second embodiment.

FIG. 11 is a RAM of the board 10 in the second embodiment.
It is a figure which shows the memory map in 14.

[Explanation of symbols]

10 …… Board, 11 ... CPU, 12 ... ROM, 13 ... Flash ROM, 14 …… RAM, 20 …… Main unit, 21 ... CPU, 22 ... ROM, 23 ... Flash ROM, 24 …… RAM, 25 ... IEEE1284 interface section, 26: Operation / display section, 27 ... PC interface, 30 ... Personal computer.

Claims (6)

[Claims] 1. A rewriting target RO, wherein a communication program for communicating with a data transfer source is installed in a rewriting target ROM.
In a device in which a rewriting program is installed in another ROM that is a ROM other than M, by operating the interface communication line connected to the data transfer source after the rewriting is completed, Rewriting end notifying means for notifying the end of rewriting; and the data transfer source, if the signal operation on the interface communication line is detected, it is determined that the ROM rewriting is finished, and the communication restoring means for returning the communication. Characteristic memory rewrite control system. 2. A rewriting target ROM is mounted with a communication program for communicating with a data transfer source, and the rewriting target RO is provided.
In a device in which a rewriting program is installed in another ROM that is a ROM other than M, by operating the interface communication line connected to the data transfer source after the rewriting is completed, A device equipped with a rewriting program in a memory rewriting control system, which has a rewriting end notifying means for notifying the end of rewriting. 3. A rewriting target ROM, wherein a communication program for communicating with a data transfer source is mounted on a rewriting target ROM.
In a device that has a rewriting program installed in another ROM that is a ROM other than M, a signal on the interface communication line connected to the device that has the rewriting program installed after the rewriting is completed. A data transfer source device in a memory rewriting control system, characterized in that it has a communication resuming means for resuming communication, assuming that ROM rewriting is completed when an operation is detected. 4. The rewriting target RO is equipped with a communication program for communicating with a data transfer source in a rewriting target ROM.
In a device in which a rewriting program is installed in another ROM that is a ROM other than M, by operating the interface communication line connected to the data transfer source after the rewriting is completed, Rewriting the end of rewriting; when the data transfer source detects a signal operation on the interface communication line, it is determined that the ROM rewriting is completed, and communication is restored. Memory rewriting method in control system. 5. The rewriting target RO is provided with a communication program for communicating with a data transfer source mounted on a rewriting target ROM.
In a device in which a rewriting program is installed in another ROM that is a ROM other than M, by operating the interface communication line connected to the data transfer source after the rewriting is completed, A memory rewriting method in a memory rewriting control system characterized by notifying the end of rewriting. 6. A rewriting target RO, wherein a communication program for communicating with a data transfer source is mounted on a rewriting target ROM.
In a device that has a rewriting program installed in another ROM that is a ROM other than M, a signal on the interface communication line connected to the device that has the rewriting program installed after the rewriting is completed. A memory rewriting method in a memory rewriting control system, characterized in that when the operation is detected, the ROM rewriting is considered to be completed and communication is restored.