PIC18CXX2
TSTFSZ
Syntax:
Test f, skip if 0
[ label ] TSTFSZ f,a
0 ≤ f ≤ 255
XORLW
Exclusive OR literal with WREG
Syntax:
[ label ]
XORLW k
Operands:
Operands:
Operation:
0 ≤ k ≤ 255
a
[0,1]
(WREG) .XOR. k → WREG
Operation:
skip if f = 0
None
Status Affected:
Encoding:
N,Z
Status Affected:
Encoding:
0000
1010
kkkk
kkkk
0110
011a
ffff
ffff
Description:
Description:
If ’f’ = 0, the next instruction,
The contents of WREG are
fetched during the current instruc-
tion execution, is discarded and a
NOPis executed making this a two-
cycle instruction. If ’a’ is 0, the
Access Bank will be selected, over-
riding the BSR value. If ’a’ is 1,
then the bank will be selected as
per the BSR value (default).
XOR’ed with the 8-bit literal 'k'.
The result is placed in WREG.
Words:
Cycles:
1
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
literal ’k’
Process
Data
Write to
WREG
Words:
Cycles:
1
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction
Example:
XORLW0xAF
= 0xB5
Before Instruction
Q Cycle Activity:
Q1
WREG
Q2
Q3
Q4
After Instruction
Decode
Read
register ’f’
Process
Data
No
operation
WREG
=
0x1A
If skip:
Q1
Q2
Q3
Q4
No
No
No
No
operation
operation
operation
operation
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
No
No
No
No
operation
operation
operation
operation
No
No
No
No
operation
operation
operation
operation
HERE
NZERO
ZERO
TSTFSZ CNT, 1
:
Example:
:
Before Instruction
PC = Address(HERE)
After Instruction
If CNT
=
=
≠
=
0x00,
PC
If CNT
PC
Address (ZERO)
0x00,
Address (NZERO)
7/99 Microchip Technology Inc.
Preliminary
DS39026B-page 233
MICROCHIP [ MICROCHIP ]
