H8S2268_09 Datasheet, PDF (574/712 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2200 Series

Section 20 ROM
20.7 Flash Memory Emulation in RAM
A setting in the RAM emulation register (RAMER) enables part of RAM to be overlapped onto
the flash memory area so that data to be written to flash memory can be emulated in RAM in real
time. Emulation can be performed in user mode or user program mode. Figure 20.8 shows an
example of emulation of real-time flash memory programming.
1. Set RAMER to overlap part of RAM onto the area for which real-time programming is
required.
2. Emulation is performed using the overlapping RAM.
3. After the program data has been confirmed, the RAMS bit is cleared, thus releasing the RAM
overlap.
4. The data written in the overlapping RAM is written into the flash memory space.
Start of emulation program
Set RAMER
Write tuning data to overlap
RAM
Execute application program
No
Tuning OK?
Yes
Clear RAMER
Write to flash memory
emulation block
End of emulation program
Figure 20.8 Flowchart for Flash Memory Emulation in RAM
Rev. 5.00 Sep. 01, 2009 Page 522 of 656
REJ09B0071-0500