Zilog Z80380 Bedienungsanleitung PDF herunterladen (Seite 57)

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Z380

™

USER'S MANUAL

ZILOG

DC-8297-03

ADD

ADD (BYTE)

ADD A,src src = R, RX, IM, IR, X

Operation: A ← A + src

The source operand is added to the accumulator and the sum is stored in the accumulator.

The contents of the source are unaffected. Two’s complement addition is performed.

Flags: S: Set if the result is negative; cleared otherwise

Z: Set if the result is zero; cleared otherwise

H: Set if there is a carry from bit 3 of the result; cleared otherwise

V: Set if arithmetic overflow occurs, that is, if both operands are of the same sign and the

result is of the opposite sign; cleared otherwise

N: Cleared

C: Set if there is a carry from the most significant bit of the result; cleared otherwise

Addressing Execute

Mode Syntax Instruction Format Time Note

R: ADD A,R 10000-r- 2

RX: ADD A,RX 11y11101 1000010w 2

IM: ADD A,n 11000110 ——n— 2

IR: ADD A,(HL) 10000110 2+r

X: ADD A,(XY+d) 11y11101 10000110 ——d— 4+r I

Field Encodings: r: per convention

y: 0 for IX, 1 for IY

w: 0 for high byte, 1 for low byte

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Zilog Z80380 Bedienungsanleitung Seite 57