Mitsubishi MELSEC-A series, Programming Manual

Page: 357 / 508

8. MICROCOMPUTER MODE
8
−
7
MELSEC-A
8.3.3 Differences in operations called by microcomputer instructions according to CPU models
Microcomputer instruction processing operation differs according to the CPU to be
used.
(1) REP LODSW, REP LODSB instructions
(a) AnSHCPU and A1FXCPU
Disregarding the value at CX register, the contents of memory indicated by
the S1 register are sent only once to AL (8-bit operation) or AX (16-bit
operation) register.
(b) CPU other than AnSHCPU and A1FXCPU
The contents of memory indicated by the S1 register are sent to AL (8-bit
operation) or AX (16-bit operation) register by the number of times specified
by the CX register.
After the execution of the instruction, the value at CX register is cleared to
"0".
To use CPU other than AnSHCPU and A1FXCPU same as AnSHCPU and
A1FXCPU, refer to the following example program.
CPU other than AnSHCPU and A1FXCPU AnSHCPU and A1FXCPU
STD
MOV
CX.3
REP LODSB
STD
MOV CX.3
A: REP LODSB
Loop A
<Example program>