r5f21346mnfp Renesas Electronics Corporation., r5f21346mnfp Datasheet - Page 688

• Manufacturer Part Number: r5f21346mnfp
• Description: Single-chip Mcus Incorporates The R8c Cpu Core
• Manufacturer: Renesas Electronics Corporation.

R8C/34M Group
R01UH0131EJ0100 Rev.1.00
Jun 21, 2011
Figure 32.14
32.4.11.5 Lock Bit Program Command
This command is used to set the lock bit of any block in the program ROM area to 0 (locked).
When 77h is written in the first bus cycle and D0h is written in the second bus cycle to the starting block
address, 0 is written to the lock bit of the specified block. Make sure the address value in the first bus cycle is
the same address as the starting block address specified in the second bus cycle.
Figure 32.14 shows a Lock Bit Program Flowchart. The lock bit status (lock bit data) can be read using the read
lock bit status command.
The FST7 bit in the FST register can be used to confirm whether writing to the lock bit has completed.
Refer to 32.4.10 Data Protect Function for the lock bit function and how to set the lock bit to 1 (not locked).
Lock Bit Program Flowchart
Write the command code 77h
Write D0h to the starting
block address
Full status check
Completed
FST7 = 1?
Start
Yes
No
FST7: Bit in FST register
32. Flash Memory
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