HD64F3337YCP16V Datasheet, PDF (506/749 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

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'F77F
H'F780
Overlapped _H'F880
RAM
H'F8FF
On-chip
RAM area
H'FF7F
Procedure
1. Overlap part of RAM (H'F880 to H'F8FF) 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'F880 to H'F8FF out externally, then program
the flash memory area, using this data as part of the program data.
Figure 20.12 Example of RAM Overlap
474