eZ80 CPU - writeframeofmind.biz

eZ80 CPU
User Manual
141
TSTIO n
Test I/O byte
Operation
Description
(0,C) • n
The contents of the C register are placed on the address bus with address (15-
8) as zeros. The I/O at this address is bitwise AND’ed with the immediate n
value and the flags are set to 1.
Condition Bits Affected
S
Z
H
P/V
N
C
Set if result is negative; reset otherwise.
Set if result is zero; reset otherwise.
Set.
Set if parity is even; reset otherwise.
Reset.
Reset.
Mnemonic Operands ADL Mode Cycles Op Codes
TSTIO n X 4 ED, 74, nn
UM007701-1100