
R8C/36T-A Group
26. Flash Memory
Under development Preliminary document
Specifications in this document are tentative and subject to change.
R01UH0240EJ0010 Rev.0.10
Page 644 of 728
Aug 05, 2011
26.5.7.3
Program Command
The program command is used to write data to the flash memory in 1-byte units.
When 40h is written in the first bus cycle and data is written in the second bus cycle to the write address, auto-
programming (data program and verify operation) starts. Make sure the address value specified in the first bus
cycle is the same address as the write address specified in the second bus cycle.
The FST7 bit in the FST register can be used to confirm whether auto-programming has completed. The FST7
bit is set to 0 during auto-programming and is set to 1 when auto-programming completes.
After auto-programming has completed, the auto-program result can be confirmed by the FST4 bit in the FST
Do not perform additional writes to previously programmed addresses.
The program command targeting each block in the program ROM can be disabled using the lock bit.
The following commands are not accepted under the following conditions:
Program commands targeting data flash block A when the FMR14 bit in the FMR1 register is set to 1 (rewrite
disabled).
Program commands targeting data flash block B when the FMR15 bit is set to 1 (rewrite disabled).
Program commands targeting data flash block C when the FMR16 bit is set to 1 (rewrite disabled).
Program commands targeting data flash block D when the FMR17 bit is set to 1 (rewrite disabled).
In EW1 mode, do not execute this command for any address where the rewrite control program is allocated.
When the RDYSTIE bit in the FMR0 register is set to 1 (flash ready status interrupt enabled), a flash ready
status interrupt can be generated upon completion of auto-programming. The auto-program result can be
confirmed by reading the FST register during the interrupt routine.
Figure 26.8
Program Flowchart (Flash Ready Status Interrupt Disabled)
Start
Write the command code
40h
Write data to the write
address
FST7 = 1?
Program completed
No
Yes
FST7: Bit in FST register
Full status check