HD64F3437TF16 Datasheet, PDF (536/752 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.

Differences between Boot Mode and User Programming Mode
Boot Mode
User Programming Mode
Total erase
Yes
Yes
Block erase
No
Yes
On-board update routine*
Program/program-verify
Erase/erase-verify
Program/program-verify
Note: * To be provided by the user, in accordance with the recommended algorithm.
Block Configuration: The flash memory is divided into one 2-kbyte block, one 12-kbyte block,
one 16-kbyte block, one 28-kbyte block, and four 1-kbyte blocks.
Address H'00000
60 kbytes
1 kbyte
1 kbyte
1 kbyte
1 kbyte
28 kbytes
16 kbytes
Address H'F77F
12 kbytes
2 kbytes
Figure 21.5 Flash Memory Blocks
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