HD64F3437TF16 Datasheet, PDF (656/752 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.

FLMCR—Flash Memory Control Register
• H8/3434F, H8/3437F
(Dual-power-supply flash memory only)
H'80
Flash memory
Bit
7
6
5
4
3
2
1
0
V_PP
—
—
—
EV
PV
E
P
Initial value
0
0
0
0
0
0
0
0
Read/Write
R
—
—
—
R/W
R/W
R/W
R/W
Program Mode
0 ^{Exit from program mode}
1 ^{Transition to program mode}
Erase Mode
0 Exit from erase mode
1 Transition to erase mode
Program-Verify Mode
0 Exit from program-verify mode
1 Transition to program-verify mode
Erase-Verify Mode
0 Exit from erase-verify mode
1 Transition to erase-verify mode
Programming Power
0 12 V is not applied to FV_PP
1 12 V is applied to FV_PP
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