RL78/F13, F14 CHAPTER 3 CPU ARCHITECTURE
R01UH0368EJ0210 Rev.2.10 118
Dec 10, 2015
3.1.2 Mirror area
The RL78/F13 and RL78/F14 mirror the code flash area of 00000H to 0FFFFH, to F0000H to FFFFFH. The products
with 96 KB or more flash memory mirror the code flash area of 00000H to 0FFFFH or 10000H to 1FFFFH, to F0000H to
FFFFFH (the code flash area to be mirrored is set by the processor mode control register (PMC)).
By reading data from F0000H to FFFFFH, an instruction that does not have the ES register as an operand can be used,
and thus the contents of the code flash can be read with the shorter code. However, the code flash area is not mirrored to
the SFR, extended SFR, RAM, data flash memory, and use prohibited areas.
See 3.1 Memory Space for the mirror area of each product.
The mirror area can only be read and no instruction can be fetched from this area.
The following show examples.
Example R5F10AmE (m = 6, A, B, G, L) (Flash memory: 64 KB, RAM: 4 KB)
Code flash memory
Code flash memory
Code flash memory
Mirror
Special-function register (SFR)
256 bytes
General-purpose register
32 bytes
RAM
4 KB
Data flash memory
Mirror
(same data as 02000H to 0EEFFH)
Special-function register (2nd SFR)
2 KB
Reserved
Reserved
FFFFFH
00000H
FFF00H
FFEFFH
FFEE0H
FFEDFH
F0800H
F07FFH
F0000H
EFFFFH
F1000H
F0FFFH
02000H
04FFFH
0EF00H
0EEFFH
F2000H
F1FFFH
10000H
0FFFFH
FEF00H
FEEFFH
For example, 0E789H is mirrored to
FE789H.
Data can therefore be read by
MOV A, !E789H, instead of
MOV ES, #00H and
MOV A, ES:!E789H.
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