SH7052 Datasheet, PDF (797/919 Pages) Renesas Technology Corp – SuperHTM RISC engine

H'00000
EB0
H'01000
EB1
H'02000
EB2
H'03000
EB3
H'04000
EB4
H'05000
EB5
H'06000
EB6
H'07000
EB7
H'08000
This area can be accessed
from both the RAM area
and flash memory area
Flash memory
H'FFFF8000
H'FFFF8FFF
EB8 to EB13
H'5FFFF
On-chip RAM
H'FFFFBFFF
Figure 21.18 Example of RAM Overlap Operation
Example in which Flash Memory Block Area EB0 is Overlapped
1. Set bits RAMS and RAM2 to RAM0 in RAMER to 1, 0, 0, 0, to overlap part of RAM onto the
area (EB0) for which real-time programming is required.
2. Real-time programming is performed using the overlapping RAM.
3. After the program data has been confirmed, the RAMS bit is cleared, releasing RAM overlap.
4. The data written in the overlapping RAM is written into the flash memory space (EB0).
Notes: 1. When the RAMS bit is set to 1, program/erase protection is enabled for all blocks
regardless of the value of RAM2 to RAM0 (emulation protection). In this state, setting
the P1 or E1 bit in flash memory control register 1 (FLMCR1) will not cause a
transition to program mode or erase mode. When actually programming or erasing a
flash memory area, the RAMS bit should be cleared to 0.
2. A RAM area cannot be erased by execution of software in accordance with the erase
algorithm while flash memory emulation in RAM is being used.
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