RC
Chapter
3.
Instruction
Set
Example:
Assume
that
the accumulator contains the value
OAAH
and the carry flag
is
Lero. The following diagrams illus-
trate
the effect
of
the RAR in',truction:
Before:
Carry
o
Accumulator·
o
o o o
After: Carry
Accumulator
1
0
o
o o
RETURN
IF
CARRY
The
RC
instruction tests the carry flag.
If
the
fldg
is
set to one to indicate a Cdrry, the instruction pops two
bytes
off
the stack and places them
in
the program counter. Program execution resumes
at
the new address
in
the program counter. If the flag i, Lero, program execution simply
continue,
with the next ,equential instruction.
Op co
de
Opemnd
RC
Operands are not permitted with the
RC
instruction.
o
Cycles:
Stdtes:
Addressing:
Flags:
Example:
o 0 0 I
1 or 3
5 or
11
(6 or 12 on
8(85)
register indirect
nOlle
For the sake
of
brevity, an example i, given for the RET instruction but not for each of
ib
closely related
variants.
347
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