HD64F3437TF16 Datasheet, PDF (445/752 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.

Example of Emulation of Real-Time Flash-Memory Update
H'0000
Small-block
area (SB1)
H'007F
H'0080
H'00FF
H'0100
Overlapped RAM
Flash memory
address space
H'7FFF
H'FB80
Overlapped _H'FC80
RAM
H'FCFF
H'FF7F
On-chip
RAM area
Procedure
1. Overlap part of RAM (H'FC80 to H'FCFF) onto the area requiring real-time update (SB1).
(Set WSCR bits 7 and 6 to 01.)
2. Perform real-time updates in the overlapping RAM.
3. After finalization of the update data, clear the RAM overlap (by clearing the RAMS and
RAM0 bits).
4. Read the data written in RAM addresses H'FC80 to H'FCFF out externally, then program
the flash memory area, using this data as part of the program data.
Figure 19.12 Example of RAM Overlap
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