NEC PD754244 Network Card User Manual


 
CHAPTER 11 INSTRUCTION SET
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User’s Manual U10676EJ3V0UM
ADDC A, @HL
Function: A, CY A+ (HL) +CY
Adds the contents of the data memory addressed by register pair HL to the contents of the A register, including
the carry flag. If a carry occurs as a result, the carry flag is set; if not, the carry flag is reset.
If the ADDS A, #n4 instruction is placed next to this instruction, and if a carry occurs as a result of executing this
instruction, the ADDS A, #n4 instruction is skipped. If a carry does not occur, the ADDS A, #n4 instruction is executed,
and a function that disables the skip function of the ADDS A, #n4 instruction is effected. Therefore, these instructions
can be used in combination for base number adjustment (refer to 11.1.4 Base number adjustment instruction).
ADDC XA, rp’
Function: XA, CY XA + rp’ + CY
Adds the contents of register pair rp’ (XA, HL, DE, BC, XA’, HL’, DE’, or BC’) to the contents of register pair XA,
including the carry. If a carry occurs as a result, the carry flag is set; if not, the carry flag is reset.
ADDC rp’1, XA
Function: rp’1, CY rp’1+XA+CY
Adds the contents of register pair XA to the contents of register pair rp’1 (HL, DE, BC, XA’, HL’, DE’, or BC’), including
the carry flag. If a carry occurs as a result, the carry flag is set; if not, the carry flag is reset.
SUBS A, @HL
Function: A A – (HL); Skip if borrow.
Subtracts the contents of the data memory addressed by register pair HL from the contents of the A register, and
sets the result to the A register. If a borrow occurs as a result, the next instruction is skipped.
The carry flag is not affected.