JP2827594B2 - Firmware online update method for microprocessor device and update method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a firmware online update method for a microprocessor device and a method for updating the same.
Respect law, the microprocessor device you Keru, the firmware update system using a rewritable ROM online operated by particular command instruction of the host device
And its updating method .

[0002]

2. Description of the Related Art Conventionally, online updating of firmware of a microprocessor device is performed by storing a ROM for IPL and an RA for user application in the microprocessor device.
M at initialization of the microprocessor device.
There was a mechanism for downloading a user application from the host processor to the AM.

[0003]

The above-mentioned conventional firmware online update method has a drawback that the user application cannot be immediately started when the power is turned on because the user application is stored in the RAM.

[0004]

According to the present invention, there is provided a firmware online update method for a microprocessor device, comprising: a microprocessor controlling a communication with the host device in a microprocessor device operated according to a command instruction from the host device; A rewritable ROM section having a ROM for storing an application program in a rewritable manner and holding the same even when the power is turned off, and activating the application program in the rewritable ROM section when the power is turned on, and via the communication control section. A command for validating a rewrite instruction from the higher-level device to the rewritable ROM unit.
When the command is received, the application program
The once stopped, waiting for reception of the application program to write conversion <br/> for example from the host device for a predetermined time, before
Application program for rewriting within a certain time
If you do not receive the application,
Restart the Deployment program, the case of receiving the application program for rewriting within a predetermined time to rewrite the ROM by sending before Symbol rewritable ROM part, application this that rewritten
Program determines whether to work properly, waits for reception of the application program for rewriting again detects an abnormality, the write confirms that it works correctly conversion
And a microprocessor section for activating the obtained application program . In the above configuration,
And the microprocessor unit comprises an OS and a monitor processor.
ROM storing the program, the OS and the monitor program.
RAM space used by RAM and the application
・ The user RAM space used by the program is held independently.
RAM based on the OS and the monitor program
A microprocessor for controlling each part;
The application from the host device is stored in the basic RAM space of the AM.
Indicates whether or not the instruction to rewrite the
Is set to a predetermined value when the power is turned on.
After that, it has key data that can set a value from the host device.
Configuration.

[0005] The fur of the microprocessor device of the present invention
The firmware and online update method is based on the OS and monitor
Application programs that run under program control
Write that stores the rewritable ram and retains it even when the power is turned off
In a microprocessor device with replaceable ROM
Application program in the rewritable ROM.
Rewrite the program online from the host device.
Firmware online update method,
Always check when starting OS and monitor program
Application data in the rewritable ROM.
Whether the rewrite instruction of the solution program is valid or invalid.
Storage area for storing key data
When the power is turned on, the key data
Start the OS and monitor program after setting
The application in the rewritable ROM can be
Application program as it is, and
After launching the installation program, the host
A command to enable a rewrite instruction for a rewritable ROM
Command, the key data is set to a value indicating validity.
And restart the OS and monitor program
The application in the rewritable ROM is
Before restarting the application program.
Application program for rewriting from the host device
Waits for a program to be rewritten, and
If you do not receive the application program,
Application programs in replaceable ROM
Reboot as it is, and within the specified time, rewrite
If an application program is received,
Rewrite the replaceable ROM, this rewritten application
Judge whether the application program operates normally.
Is detected, the application program for rewriting is
Wait for the program to be received and confirm that it operates normally
And this rewritten application program
Start up and set the key data to a value indicating invalid.
There is a step of resetting.

[0006]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention. The microprocessor 1 includes, via a bus 7, a RAM 2, which is a volatile memory that is readable and writable, a ROM 3, which is a read-only memory, and a rewritable ROM 4, which is a read-only memory that can be completely erased and then rewritten. A ROM rewriting control circuit 5 for controlling data rewriting of the rewritable ROM 4 and a communication control circuit 6 for controlling communication with the host processor. The microprocessor 1 can be reset from the outside via a reset port 11. Further, the RAM 20 is separated into a basic RAM space 21 used by the OS and the monitor, and a user RAM space 22 used by a user application.

Before the power of the microprocessor device is turned on, the OS and the monitor program are stored in the ROM 3, and the rewritable ROM 4 stores the version n.
Are stored. This user program can operate on the OS.

Next, the operation of the embodiment shown in FIG. 1 will be described with reference to the state transition diagram of the firmware online update system of the present invention shown in FIG.

If it is assumed that the power of this apparatus in the power-off state (state S100) is turned on (state S101), R
The OS in the OM3 detects the power-on and detects the basic RA of the RAM2.
The key data for instructing the ROM rewrite in the M space 21 is set as “invalid”. Thereafter, the monitor in the ROM 3 is started (state S102), the key data check (state S103) detects that this key data is "invalid", and the active state in version n (state S102).
107). In this state, the command instruction from the upper processor can be received by the communication control circuit 6 via the communication port 61, and the corresponding processing can be performed.

Next, the operation when the user program is rewritten online from the version n + 1 and the upper processor will be described.

An active state (state S1) in version n
07), a key setting command is instructed by the upper processor, and the microprocessor 1 sets key data for which the ROM rewriting instruction is “valid” in the basic RAM space 21 of the RAM 2. It is assumed that the RAM 2 is not initialized by reset, but is initialized only by turning on the power.

Next, an initialization command is instructed by the host processor, and the system restarts from the start-up of the OS (state S101).
It launched a monitor (state S102), to migrate to the key data checking state (S103). Currently, because the key data remains set to "valid", a state of waiting for an instruction from the host processor (state S104) to check the "valid" key.

Here, if there is no instruction from the upper processor for a certain period, a timeout occurs and the version n
To the active state (state S107), and an error message is notified to the upper processor.

If a higher-level processor instructs ROM rewriting, the ROM rewriting control circuit 5 is activated to update the rewritable ROM 4 to version n + 1. After the update is completed, the update state (state S105)
And waits for a temporary activation permission instruction from the upper processor. When a temporary permission instruction is issued from the upper processor in the update state, the version n + 1 of the user application
The program is activated (state S106), and reception and processing of a user command become possible.

When it is confirmed that the user application program operates normally, the key data of the ROM rewrite instruction is "invalid" from the host processor.
Is issued, and the state shifts to the active state (state S107) in version n + 1.

However, if a bug is mixed in the version n + 1 or if an error is mixed in the ROM rewriting process, a malfunction may occur. In such a case, there are two types of cases: an emergency interrupt is generated in an infinite loop to restart the initialization by autonomous interruption, and an initialization that cannot be restarted autonomously and is reset from the outside via the reset port 2 to initialize. Can be In any case, since there is no change in the OS , the monitor, and the key data , the state normally transitions to the key data check state (state S103), the validity of the key is checked, and the state shifts to the instruction waiting state (state S104) again. . After that, the state shown in FIG.
The above processing is repeated according to the transition sequence.

[0018] where do again written from the host processor the user program version n + 1 correctly, the higher
Processor holds version n or earlier program
If so, the microprocessor device can be restored , for example, by writing version n.

[0019]

As described above, the present invention has a rewritable ROM that stores an application program in a rewritable manner and retains the program even when the power is turned off. Judgment is made whether the application program has been rewritten normally, and if there is an error, rewriting control is repeated until it becomes normal, so that the program should be started up promptly without time to download the program at initialization such as turning on the power of the microprocessor device. And the firmware update procedure can be introduced.

Further, by providing a means for recovering from a failure that may occur when rewriting a program in a rewritable ROM, there is an effect that the firmware can be updated from a remote place with ease.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a state transition diagram showing an operation sequence of the embodiment of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Microprocessor 2 RAM 21 Basic RAM space 22 User RAM space 3 ROM 4 Rewritable ROM 5 ROM rewrite control circuit 6 Communication control circuit 7 Bus 11 Reset port 61 Communication port with host processor

Claims (3)

(57) [Claims] 1. A microprocessor device that operates in accordance with a command instruction of a higher-level device, a communication control unit that controls communication with the higher-level device, and a ROM that stores an application program in a rewritable manner and retains the application program even when power is turned off. A rewritable ROM section having: a command to activate the application program of the rewritable ROM section at power-on, and to enable a rewrite instruction to the rewritable ROM section from the host device via the communication control section. It said to be receiving a
The application program is temporarily stopped, and the application program for rewriting from the host
Wait for the program to be received and rewrite within the fixed time
If you do not receive the application program for
Restart the stopped application program
Dynamic and, the case of receiving the application program for rewriting within a predetermined time can before Symbol rewritable RO
By sending the M unit to rewrite the ROM, the rewritten application program determines whether to work properly, waits for reception of abnormal application program for re-rewriting detects, operates normally
Make sure that this rewritten application
A firmware online update method for a microprocessor device, comprising: a microprocessor section for starting a program . 2. The system according to claim 1, wherein the microprocessor unit has a ROM storing an OS and a monitor program, and a RAM independently having a basic RAM space used by the OS and the monitor program and a user RAM space used by the application program. , and a microprocessor for controlling the respective units based on the OS and the monitor program, the basic RAM space of the RAM, from the host device
Application program rewrite instruction is valid
Is set to a predetermined value at power-on to indicate
After turning on the power, a key that can set a value from the host
Firmware online update scheme of the microprocessor system according to claim 1, characterized in that chromatic data. 3. Under the control of an OS and a monitor program
Application to run Rewrite the program
Has a rewritable ROM that is stored in the
The rewritable microprocessor device,
Of application program in ROM
From the host device online
In the online update method, Be sure to check when starting up the OS and monitor program.
Data in the rewritable ROM
Application program rewrite instruction is valid or invalid
Storage area for storing key data indicating
Keep in mind At power-on, set the key data to a value indicating invalid
Before starting the OS and monitor program
From the application in the rewritable ROM,
Start the program as it is, After starting the application program,
Rewriting finger for the rewritable ROM from the
Key data is received when a command to enable
After setting to a value indicating validity, the OS and monitor program
By restarting the RAM, the rewritable RO
Before restarting the application program in M
An application for rewriting from the host
Wait for the program Within the fixed time, the application program for rewriting
If no program is received, the rewritable ROM
Restart the application program as it is, Within the fixed time, the application program for rewriting
When a program is received, the rewritable ROM is written.
This rewritten application program
Determine whether the ram operates normally, When an error is detected, the application for rewriting
Wait for the program to be received, After confirming normal operation, this rewritten
Start the application program and
Key data is reset to a value indicating invalidity.
Microprocessor device firmware online
Update method.