CP
Chapter
3.
Instruction
Set
1 1
0
Cycles:
States:
Addressing:
Flags:
Example:
0 0 1 0 0
low addr
high
addr
3 or 5
(2
or 5 on 8085)
11
or 17
(9
or 18 on 8085)
immediate/register indirect
none
For the sake
of
brevity, an example
is
given for the CALL im.truction
but
not for each
of
its closely related
variants.
CALL
IF POSITIVE
The
CP
instruction combines features
of
the J P and
PUSH
instructions.
CP
tests the setting
of
the sign flag. If
the flag
is
set
to
zero (indicating that the contents of the accumulator are positive),
CP
pushes the contents
of
the program
counter
onto
the stack and then jumps to the address specified
by
the
CP
instruction. If the flag
is
set to one, program execution simply continues with the next sequential instruction.
Opcode Operand
CP
address
Although the use
of
a label
is
more common, the address may also
be
specified
as
a number or an expression.
1 1 1
Cycles:
S ta tes:
Ad
dressi
ng:
Flags:
Example:
1
0
1
0 0
low address
high addr
3 or 5
(2
or 5 on 8085)
11
or 17
(9
or 18 on 8085)
im
mediate/register indirect
none
For the sake
of
brevity, an example
is
given for the CALL instruction but not for each
of
its closely related
variants.
3-15
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