
UM008007-0715 Z80 Instruction Description
Z80 CPU
User Manual
143
ADD A, r
Operation
A ← A + r
Op Code
ADD
Operands
A, r
Description
The contents of register r are added to the contents of the Accumulator, and the result is
stored in the Accumulator. The r symbol identifies the registers A, B, C, D, E, H, or L,
assembled as follows in the object code:
Condition Bits Affected
S is set if result is negative; otherwise, it is reset.
Z is set if result is 0; otherwise, it is reset.
H is set if carry from bit 3; otherwise, it is reset.
Register r
A111
B000
C001
D010
E011
H100
L101
M Cycles T States 4 MHz E.T.
141.00
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