NEC PD754244 Manuel D’Utilisation

User’s Manual  U10676EJ3V0UM

Function:  A 

←

 A+n4; Skip if carry. n4 = l

3-0

: 0 to FH

Adds 4-bit immediate data n4 to the contents of the A register.  If a carry occurs as a result, the next instruction

is skipped.  The carry flag is not affected.

If this instruction is used in combination with ADDC A, @HL or SUBC A, @HL instruction, it can be used as a base

number adjustment instruction (refer to 11.1.4 Base number adjustment instruction).

Function:  XA 

←

 XA+n8; Skip if carry. n8 = I

7-0

: 00H to FFH

Adds 8-bit immediate data n8 to the contents of register pair XA.  If a carry occurs as a result, the next instruction

is skipped.  The carry flag is not affected.

Function:  A 

← A + (HL); Skip if carry.

Adds the contents of the data memory addressed by register pair HL to the contents of the A register.  If a carry

occurs as a result, the next instruction is skipped.  The carry flag is not affected.

Function:  XA 

← XA + rp’; Skip if carry.

Adds the contents of register pair rp’ (XA, HL, DE, BC, XA’, HL’, DE’, or BC’) to the contents of register pair XA.

If a carry occurs as a result, the next instruction is skipped.  The carry flag is not affected.

Function:  rp’ 

←

 rp’1 + XA; Skip if carry.

Adds the contents of register pair XA to register pair rp’1 (HL, DE, BC, XA’, HL’, DE’, or BC’).  If a carry occurs

as a result, the next instruction is skipped.  The carry flag is not affected.

To shift a register pair to the left

MOV

XA, rp’1

ADDS

rp’1, XA

NOP