HD64F3437TF16 Datasheet, PDF (425/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

19.4.3 Programming Flowchart and Sample Program
Flowchart for Programming One Byte
Start
Set erase block register
(set bit of block to be programmed to 1)
Write data to flash memory (flash
memory latches write
address and data)^*1
n=1
Enable watchdog timer^*2
Select program mode
(P bit = 1 in FLMCR)
Wait (x) µs^*4
Clear P bit
Disable watchdog timer
Select program-verify mode
(PV bit = 1 in FLMCR)
Wait (t_VS1) µs^*4
Verify^*3 (read memory)
OK
Clear PV bit
End of programming
Notes: *1 Write the data to be programmed
with a byte transfer instruction.
*2 Set the timer overflow interval to the
shortest value (CKS2, CKS1, CKS0
all cleared to 0).
*3 Read the memory data to be verified
with a byte transfer instruction.
*4 x: 10 to 20 µs
t_VS1: 4 µs or more
N: 50 (set N so that total
programming time does not
exceed 1 ms)
No go
Clear PV bit
End of verification
Clear erase block register
(clear bit of programmed block to 0)
End (1-byte data programmed)
No
n ≥ N?^*4
Yes
Programming error
n+1→n
Figure 19.8 Programming Flowchart
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