Mirror Area - NEC 78K0R/KE3 User Manual

3.1.2 Mirror area

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The PD78F1142 and 78F1142A mirror the data flash area of 00000H to 0FFFFH, to F0000H to FFFFFH.
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The PD78F1143, 78F1143A, 78F1144, 78F1144A, 78F1145, 78F1145A, 78F1146, 78F1146A mirror the data
flash area of 00000H to 0FFFFH or 10000H to 1FFFFH, to F0000H to FFFFFH (the data 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 registers as an operand can be
used, and thus the contents of the data flash can be read with the shorter code. However, the data flash area is not
mirrored to the SFR, extended SFR, RAM, 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.
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Example 1 PD78F1142, 78F1142A
(Flash memory: 64 KB, RAM: 4 KB)
Setting MAA = 0
F F F F F H
Special-function register
F F F 0 0 H
F F E F F H
General-purpose register
32 bytes
F F E E 0 H
FFEDFH
F E F 0 0 H
FEEFFH
Flash memory
(same data as 01000H to 0EEFFH)
F 1 0 0 0 H
F 0 F F F H
F 0 8 0 0 H
F 0 7 F F H
Special-function register (2nd
F 0 0 0 0 H
E F F F F H
1 0 0 0 0 H
0 F F F F H
Flash memory
0 E F 0 0 H
0 E E F F H
Flash memory
0 1 0 0 0 H
0 0 F F F H
Flash memory
0 0 0 0 0 H
Remark MAA: Bit 0 of the processor mode control register (PMC).
PMC register is described below.
CHAPTER 3 CPU ARCHITECTURE
(SFR)
256 bytes
RAM
4 KB
Reserved
SFR)
2 KB
Mirror
Reserved
For example, 02345H is mirrored to
F2345H. Data can therefore be read by
MOV A, !2345H, instead of MOV ES,
#00H and MOV A, ES:!2345H.
User's Manual U17854EJ9V0UD
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Example 2 PD78F1146, 78F1146A
(Flash memory: 256 KB, RAM: 12 KB)
Setting MAA = 1
F F F F F H
Special-function register (SFR)
256 bytes
F F F 0 0 H
F F E F F H
General-purpose register
32 bytes
F F E E 0 H
FFEDFH
RAM
12 KB
F C F 0 0 H
FCEFFH
Flash memory
(same data as 11000H to 1CEFFH)
F 1 0 0 0 H
F 0 F F F H
Reserved
F 0 8 0 0 H
F 0 7 F F H
Special-function register (2nd SFR)
2 KB
F 0 0 0 0 H
E F F F F H
Reserved
4 0 0 0 0 H
3 F F F F H
For example, 15432H is mirrored to
F5432H. Data can therefore be read by
Flash memory
MOV A, !5432H, instead of MOV ES,
#01H and MOV A, ES:!5432H.
1 C F 0 0 H
1CEFFH
Flash memory
1 1 0 0 0 H
1 0 F F F H
Flash memory
0 0 0 0 0 H
Mirror
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