UPD753108 Datasheet, PDF (391/459 Pages) NEC – 4-bit Single-chip Microcontrollers

CHAPTER 11 INSTRUCTION SET
MOV A, @HL
MOV A, @HL+
MOV A, @HL–
MOV A, @rpa1
Function: A ← (Register pair specified with an operand)
when register pair = HL+ : skip if L = 0
when register pair = HL– : skip if L = FH
Transfers the contents of the data memory addressed by a register pair (HL, HL+, HL–, DE, or DL) to the A register.
If autoincrement (HL+) is specified as a register pair, the contents of the L register are automatically incremented
by one after the data has been transferred. If the contents of the L register become 0 as a result, the next one
instruction is skipped.
If autodecrement (HL–) is specified as a register pair, the contents of the L register are automatically decremented
by one after the data has been transferred. If the contents of the L register become FH as a result, the next one
instruction is skipped.
MOV XA, @HL
Function: A ← (HL), X ← (HL + 1)
Transfers the contents of the data memory addressed by register pair HL to the A register, and the contents of
the next memory address to the X register.
If the contents of the L register are an odd number, an address whose least significant bit is ignored is transferred.
Application example
To transfer the data at addresses 3EH and 3FH to register pair XA
MOV HL, #3EH
MOV XA, @HL
MOV @HL, A
Function: (HL) ← A
Transfers the contents of the A register to the data memory addressed by register pair HL.
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