
R8C/3GM Group
31. Flash Memory
R01UH0284EJ0100 Rev.1.00
Aug 09, 2011
31.4.7
Suspend Operation
The suspend function halts the auto-erase operation temporarily during auto-erasure.
When suspending the auto-erasure of any block in data flash, auto-programming and reading another block
can be executed.
When suspending the auto-erasure of data flash, auto-programming and reading program ROM can be
executed.
When suspending the auto-erasure of any block in program ROM, auto-programming and reading another
block can be executed.
When suspending the auto-erasure of program ROM, auto-programming and reading data flash can be
executed.
To check the suspend, verify the FST7 bit is set to 1 (ready), then verify the FST6 bit is set to 1 (during erase-
suspend) to confirm whether erasure has been suspended. When the FST6 bit is set to 0 (other than erase
suspend), erasure completes.
Notes:
1. E indicates operation is enabled by using the suspend function, D indicates operation is disabled, and N/A
indicates no combination is available.
2. Operation cannot be suspended during programming.
3. The block erase command can be executed for erasure. The program, lock bit program, and read lock bit status
commands can be executed for programming.
The clear status register command can be executed when the FST7 bit in the FST register is set to 1 (ready).
The operation of block blank check is disabled during suspend.
4. The MCU enters read array mode immediately after entering erase-suspend.
5. The program ROM area can be read with the BGO function while programming or block erasing data flash.
Figure 31.3
Suspend Operation Timing
Table 31.4
Executable Operation during Suspend
Operation during Suspend
Data flash
(Block during erasure
execution before
entering suspend)
Data flash
(Block during no erasure
execution before
entering suspend)
Program ROM
(Block during erasure
execution before
entering suspend)
Program ROM
(Block during no erasure
execution before
entering suspend)
Erase Program Read Erase Program Read Erase Program Read Erase Program Read
Areas during
erasure
execution before
entering suspend
Data
flash
DD
D
E
N/A
D
E
Program
ROM
N/A
D
E
D
E
Data flash
Data
read
Suspend
(readable)
Program
Erase
Program
ROM
User
program
Command
issue
User
program
Set
FMR21
bit to 1
Command
issue
User
program
Set
FMR21
bit to 0
User
program
User
program
FMR21 bit in
FMR2 register
FST7 bit in
FST register
FST6 bit in
FST register
RDYSTI bit in
FST register
Flash ready
interrupt
handling
Suspend
(readable)
Flash ready
interrupt
handling
User
program
Flash ready
interrupt
handling
Suspend
(readable)
Set to 0 by a program.
td(SR-SUS)
1 is set automatically.
Erase
1 is set automatically.