Dec iy – Zilog Z08470 User Manual
Page 213
UM008007-0715
Z80 Instruction Description
Z80 CPU
User Manual
201
DEC IY
Operation
IY ← IY– 1
Op Code
DEC
Operand
IY
Description
The contents of Index Register IY are decremented.
Condition Bits Affected
None.
Example
If Index Register IY contains
7649h
, then upon the execution of a DEC IY instruction,
Index Register IY contains
7648h
.
M Cycles
T States
4 MHz E.T.
2
10 (4, 6)
2.50
1
1
1
0
1
1
1
1
FD
0
0
0
1
1
0
1
1
2B