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Res reset bit – Zilog Z80380 User Manual

Page 172

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Z380

™

U

SER

'

S

M

ANUAL

DC-8297-03

Z

ILOG

RES
RESET BIT

RES b, dst

dst = R, IR, X

Operation:

dst(b)

←

0

The specified bit b within the destination operand is cleared to 0. The other bits in the
destination are unaffected. The bit to be reset is specified by a 3-bit field in the instruction;
this field contains the binary encoding for the bit number to be cleared. The bit number b
must be between 0 and 7.

Flags:

S:

Unaffected

Z:

Unaffected

H:

Unaffected

V:

Unaffected

N:

Unaffected

C:

Unaffected

Addressing

Execute

Mode

Syntax

Instruction Format

Time

Note

R:

RES b,R

11001011 10bbb -r-

2

IR:

RES b,(HL)

11001011 10bbb110

2+r

X:

RES b,(XY+d)

11y11101 11001011 ——d— 10bbb110

4+r

I

Field Encodings:

r:

per convention

y:

0 for IX, 1 for IY

See also other documents in the category Zilog Sensors: