Difference between revisions of "ADD"

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(add a,reg8)
(add a,reg8)
Line 12: Line 12:
 
*$86: add a,(hl)
 
*$86: add a,(hl)
 
*$87: add a,a
 
*$87: add a,a
 +
*$C6 $XX: add a,$XX
  
 
Returns:
 
Returns:
Line 18: Line 19:
 
*H - Set if carry from bit 3.
 
*H - Set if carry from bit 3.
 
*C - Set if carry from bit 7.
 
*C - Set if carry from bit 7.
 +
 +
= add hl,reg16 =
 +
Adds the contents of a 16-bit register to the contents of hl and stores the result in hl.
 +
 +
*$09: add hl,bc
 +
*$19: add hl,de
 +
*$29: add hl,hl
 +
*$39: add hl,sp
 +
 +
Returns:
 +
*Z - Unaffected.
 +
*N - Reset.
 +
*H - Set if carry from bit 11.
 +
*C - Set if carry from bit 15.
 +
 +
= add sp,2comp =
 +
Adds an 8-bit 2's complement value to sp and stores the result in sp.
 +
 +
*$E8: add sp,2comp
 +
 +
Returns:
 +
*Z - Reset.
 +
*N - Reset.
 +
*H - Set or reset according to operation.
 +
*C - Set or reset according to operation.

Revision as of 12:49, 25 February 2008

ADD is an assembly opcode.

add a,reg8

Adds the contents of an 8-bit register to the contents of accumulator and stores the result in accumulator.

  • $80: add a,b
  • $81: add a,c
  • $82: add a,d
  • $83: add a,e
  • $84: add a,h
  • $85: add a,l
  • $86: add a,(hl)
  • $87: add a,a
  • $C6 $XX: add a,$XX

Returns:

  • Z - Set if result is zero.
  • N - Reset.
  • H - Set if carry from bit 3.
  • C - Set if carry from bit 7.

add hl,reg16

Adds the contents of a 16-bit register to the contents of hl and stores the result in hl.

  • $09: add hl,bc
  • $19: add hl,de
  • $29: add hl,hl
  • $39: add hl,sp

Returns:

  • Z - Unaffected.
  • N - Reset.
  • H - Set if carry from bit 11.
  • C - Set if carry from bit 15.

add sp,2comp

Adds an 8-bit 2's complement value to sp and stores the result in sp.

  • $E8: add sp,2comp

Returns:

  • Z - Reset.
  • N - Reset.
  • H - Set or reset according to operation.
  • C - Set or reset according to operation.