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General Purpose Arithmetic And Cpu Control Groups
General Purpose Arithmetic And Cpu Control Groups
- Gunther Strube
Owned by Gunther Strube
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Mnemonic Symbolic Flags (bit 7-0) Instruction Number Number of Number of Comments
operation S Z . H . V N C opcode of bytes M cycles T states
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DAA Converts accum. ? ? X ? X P * ? 00 100 111 (27h) 1 1 4 Decimal
contents into adjust
packed BCD format accumulator
CPL A <- NOT A * * X 1 X * 1 * 00 101 111 (2Fh) 1 1 4 Complement
(1. complement) accumulator
NEG A <- 0 - A ? ? X ? X V 1 ? 11 101 101 (EDh) 2 2 8 Negate
(2. complement) 01 000 100 (44h) accumulator
CCF CY <- NOT CY * * X X X * 0 ? 00 111 111 (3Fh) 1 1 4 Complement
Carry flag
SCF CY <- 1 * * X 0 X * 0 1 00 110 111 (37h) 1 1 4 Set Carry
flag
NOP No operation * * X * X * * * 00 000 000 1 1 4
HALT CPU halted * * X * X * * * 01 110 110 (76h) 1 1 4
DI IFF <- 0 * * X * X * * * 11 110 011 (F3h) 1 1 4
EI IFF <- 1 * * X * X * * * 11 111 011 (FBh) 1 1 4
IM 0 Set int. mode 0 * * X * X * * * 11 101 101 (EDh) 2 2 8
01 000 110 (46h)
IM 1 Set int. mode 1 * * X * X * * * 11 101 101 (EDh) 2 2 8
01 010 110 (56h)
IM 2 Set int. mode 2 * * X * X * * * 11 101 101 (EDh) 2 2 8
01 011 110 (5Eh)
IFF = Interrupt enable flip-flop