HD64F2638F20J Datasheet, PDF (854/1512 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2600 Series

Section 21B ROM
(H8S/2638 Group, H8S/2639 Group, H8S/2630 Group)
H8S/2639, H8S/2638, H8S/2636,
H8S/2630, H8S/2635 Group
21B.4.5 Flash Memory Emulation in RAM
Emulation should be performed in user mode or user program mode. When the emulation block
set in RAMER is accessed while the emulation function is being executed, data written in the
overlap RAM is read.
SCI
Flash memory
Emulation block
RAM
Application program
Execution state
Overlap RAM
(emulation is performed
on data written in RAM)
Figure 21B-4 Reading Overlap RAM Data in User Mode or User Program Mode
When overlap RAM data is confirmed, the RAMS bit is cleared, RAM overlap is released, and
writes should actually be performed to the flash memory.
When the programming control program is transferred to RAM, ensure that the transfer destination
and the overlap RAM do not overlap, as this will cause data in the overlap RAM to be rewritten.
Page 804 of 1458
REJ09B0103-0800 Rev. 8.00
May 28, 2010