eZ80
®
CPU
User Manual
UM007714-0908 CPU Instruction Set
110
Bit b, r
Bit Test
Operation
Z
←
~
r
[
b
]
Description
The
r
operand is any of the 8-bit CPU registers A, B, C, D, E, H, or L. This instruction
tests bit
b
in the specified register and sets the 0 Flag (Z) if the bit is 0. The Z Flag is reset
if bit
b
of register r is a one.
Condition Bits Affected
Attributes
jj = binary code 01 bbb rrr; where rrr identifies the A, B, C, D, E, H, or L register and
bbb identifies the bit tested and assembled into the object code, as indicated in Table 46.
S Undefined.
Z Set if bit b is 0; reset otherwise.
H Set.
P/V Undefined.
N Reset.
C Not affected.
Mnemonic Operand ADL Mode Cycle Opcode (hex)
BIT b,r X2CB, jj
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