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What are the supplemental settings for M16C/62N Flash memory MCUs?

Latest Updated:02/14/2006

Question:

Supplemental Usage Notes for M16C/62N Flash memory MCUs: CPU Reprogramming Mode.
After issuing the following Usage Note, we received many requests for details on how to set [Program Command], [Lock Bit Program Command], or [Read Array Command] when occurring immediately after a program command. Please refer to the three examples below for supplemental settings in these unique circumstances.

Original Usage Note.
A command that immediately follows a program command must have the same address specified in its first bus cycle as the address specified in the second bus cycle of the preceding program command.

Answer:

Supplemental Settings

1) When [Program Command] immediately follows a program command:
Disregard the Original Usage Note and set as follows: set the same address in the first and second bus cycles for the program command

Example: When executing a program command to Addresses C0000h and C0002h
1. Write “40h” (program command) to Address C0000h.
2. Write data to Address C0000h.
3. Write “40h” (program command) to Address C0002h.
4. Write data to Address C0002h.

2) When [Lock Bit Program Command] immediately follows a program command:
Disregard the Original Usage Note and set as follows: set the block address (largest even number address) to the first and second bus cycles of the lock bit program command.

Example: When executing a lock bit program command at block 6 after executing a program command at Address C0000h
1. Write “40h” (program command) to Address C0000h.
2. Write data to Address C0000h.
3. Write “77h” (lock bit program command) to Address CFFFEh.
4. Write “D0h” (lock bit program command) to Address CFFFEh.

3) When [Read Array Command] immediately follows a program command

Example: When executing a read array command to read Address C2000h after executing a program command at Address C0000h

First, in the standard serial or parallel input/output mode, write 4 consecutive addresses (example D0000h to D0003h) to “FFFFFFFFh”. Then, switch to the CPU reprogramming mode and start the Flash memory reprogramming control. To execute a read array command immediately after a program command, execute the following:
1. Write “40h” (program command) to Address C0000h.
2. Write data to Address C0000h.
3. Write “FFh” (read array command) to Address C0000h.
4. Read Address D0000h.
5. Repeat step 4 until the result is “FFFFh”.
6. Read Address D0002h
7. Repeat step 6 until the result is “FFFFh”
8. Read Address C2000h.
Suitable Products
M16C/62N
M16C/62N(M3062GF8NFP, M3062GF8NGP)