NEC PD750008 - Manual (Page 317)

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CHAPTER 11 INSTRUCTION SET
Caution All 2-byte instructions (except the BRCB instruction and CALLF instruction) set in the
reference table must be 2-machine-cycle instructions. Pairs of 1-byte instructions can be
set as indicated in the table below.
First byte instruction Second byte instruction
INCS L
MOV A,@HL DECS L
MOV @HL,A INCS H
XCH A,@HL DECS H
INCS HL
INCS E
MOV A,@DE DECS E
INCS D
XCH A,@DE DECS D
INCS DE
MOV A,@DL INCS L
DECS L
XCH A,@DL INCS D
DECS D
The PC is not incremented during execution of a GETI instruction, so that after a reference instruction is
executed, execution is resumed starting at the address immediately after the GETI instruction.
If the instruction immediately preceding a GETI instruction has the skip function, the GETI instruction is
skipped as with other 1-byte instructions. If an instruction referenced with a GETI instruction has the skip
function, the instruction immediately following the GETI instruction is skipped.
If a GETI instruction references an instruction having a string effect, the following processing is performed:
• If the instruction immediately preceding the GETI instruction also has the string effect in the same group,
the execution of the GETI instruction cancels the string effect, and the referenced instruction is not
skipped.
• If the instruction immediately following the GETI instruction also has the string effect of the same group,
the string effect of the referenced instruction remains valid, and the next instruction is skipped.