Nintendo GAME BOY Programming Manual page 279

SYMBOLIC
MNEMONIC
OPERATION
ADD A,r A←A+r
ADD A,n A←A+n
ADD A←A+(H
A,(HL) L)
ADC A,s A←A+s+
CY
SUB s A←A-s
SBC A,s A←A-s-
CY
AND s A←AΛs
OR s AVs
XOR s A⊕s
CP s A-s
INC r r←r+1
INC (HL) (HL)
←(HL)+1
DEC r r←r-1
DEC (HL) (HL)
←(HL)-1
ADD HL←HL+
HL,ss ss
ADD SP,e SP←SP+
e
INC ss ss←ss+1
DEC ss ss←ss-1
The flag is affected according
to the result of the operation.
FLAGS
CY H N
* * 0
* * 0
* * 0
* * 0
* * 1
* * 1
0 1 0
0 0 0
0 0 0
* * 1
-- * 0
-- * 0
-- * 1
-- * 1
* * 0
* * 0
-- -- --
-- -- --
Z: Zero flag. z=1 if the result of the operation is 0
C: Carry/link flag. C=1 if the operation produced a carry
from the MSB of the operand or result
H: Half-carry flag.
N: Add/Subject flag.
Appendix 2. Register and Instruction Set Summaries
OP-CODE
CYCL 76 543 210
Z
* 1 10 000
* 2 11 000 110
n
* 2 10 000 110
* 1,2 -- --- ---
* 1,2 -- --- ---
* 1,2 -- --- ---
* 1,2 -- --- ---
* 1,2 -- --- ---
8 1,2 -- --- ---
* 1,2 -- --- ---
* 1 00 r
* 3 00 110 100
* 1 00 r
* 3 00 110 101
-- 2 00 ss1 001
0 4 11 101 000
e
-- 2 00 ss0 011
-- 2 00 ss1 011
279
COMMENT
r
s is any of r,n,(HL)
CYCL 1: s is r
2: s is n or (HL)
100
Register ss
Pair
101 BC 00
DE 01
HL 10
SP 11
e=-128~+127