eZ80
®
CPU
User Manual
UM007714-0908 CPU Instruction Set
367
TSTIO n
Test I/O Byte
Operation
{0000h, C} AND n
Description
The CPU places the contents of the C register onto the lower byte of the address bus,
ADDR[7:0], while it forces the two upper bytes of the address bus, ADDR[23:0], to 0s.
The data at this I/O address {
0000h, C}, is bitwise ANDed with the 8-bit immediate value
n
. The appropriate flags are set to 1, depending on the result of the
AND
logical operation.
Condition Bits Affected
Attributes
S Set if result is negative; reset otherwise.
Z Set if result is 0; reset otherwise.
H Set.
P/V Set if parity is even; reset otherwise.
N Reset.
C Reset.
Mnemonic Operand ADL Mode Cycle Opcode (hex)
TSTIO n X4ED, 74, nn
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