Individual Instruction Descriptions
4-90
4.14.10 CMP Compare Two Words
[label] name src, src1
[
, mod
] Clock,
clk
Word,
w
With RPT,
clk
Class
CMP A
n
, {
adrs
} Table 4–46 Table 4–46 1b
CMP A
n
[~],
imm16
[,
next A
] 2 2 N/R 2b
CMP
CMP
A
n
, A
n
~ [,
next A
]
A
n
~, A
n
[,
next A
]
1 1 n
R
+3 3
CMP
†
R
x
,
imm16
2 2 N/R 4c
CMP
†
R
x
, R5 1 1 n
R
+3 4d
†
Does not modify A
n
status
Execution [premodify AP if
mod
specified]
STAT flags set by
src – src1
operation
PC = PC +
w
Flags Affected
src
is A
n
:OF, SF, ZF, CF are set accordingly
src
is R
x
: RCF, RZF are set accordingly
src
is
{adrs}
: TAG bit is set accordingly
Opcode
Instructions 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
CMP A
n
, {
adrs
}
0 1 0 1 1 0 0 A
n adrs
x
dma16
(for direct) or
offset16
(long relative) [see section 4.13]
CMP A
n
[~],
imm16
[,
next A
]
1 1 1 0 0
next A
A
n
0 1 1 0 0 1 A~ ~A
x
imm16
CMP A
n
, A
n
~ [,
next A
] 1 1 1 0 0
next A
A
n
1 0 0 0 0 0 0 0
CMP A
n
~, A
n
[,
next A
] 1 1 1 0 0
next A
A
n
1 0 0 0 0 0 1 0
CMP R
x
,
imm16
1 1 1 1 1 1 1 0 0 0 1 1 R
x
0 0
x
imm16
CMP R
x
, R5 1 1 1 1 1 1 1 0 0 1 1 1 R
x
0 0
Description Subtract value of
src1
from
src
(i.e.,
src
–
src1
) and only modify the status flag.
Premodification of accumulator pointer is allowed with some operand types.
See Also CMPB, CMPS, J
cc
, C
cc
Example 4.14.10.1 CMP A0, *R0
Compare value at accumulator A0 and the content of data memory location pointed by R0 and change
the STAT flags accordingly.
Example 4.14.10.2 CMP A0~, 0x1400, ––A
Predecrement accumulator pointer AP0. Compare value at accumulator A0~ to immediate value at
0x1400 and change the STAT flags accordingly.
