HD6473032F16 Datasheet, PDF (591/847 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 18 ROM
18.2.4 Flash Memory Emulation in RAM
In the H8/3052BF, flash memory programming can be emulated in real time by overlapping the
flash memory with part of RAM ("overlap RAM"). When the emulation block set in RAMCR is
accessed while the emulation function is being executed, data written in the overlap RAM is read.
Emulation should be performed in user mode or user program mode.
Flash memory
Emulation block
SCI
RAM
Application program
Execution state
Overlap RAM
(emulation is performed
on data written in RAM)
Figure 18.3 Reading Overlap RAM Data in User Mode or User Program Mode
When overlap RAM data is confirmed, clear the RAMS bit to release RAM overlap, and actually
perform writes to the flash memory.
When the programming control program is transferred to RAM in on-board programming mode,
ensure that the transfer destination and the overlap RAM do not overlap, as this will cause data in
the overlap RAM to be rewritten.
Rev. 3.00 Mar 21, 2006 page 561 of 814
REJ09B0302-0300