PIC18F2450/4450
TSTFSZ
Test f, Skip if 0
XORLW
Exclusive OR Literal with W
Syntax:
TSTFSZ f {,a}
Syntax:
XORLW k
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operands:
Operation:
Status Affected:
Encoding:
Description:
0 ≤ k ≤ 255
(W) .XOR. k → W
N, Z
Operation:
skip if f = 0
Status Affected:
Encoding:
None
0000
1010
kkkk
kkkk
0110
011a
ffff
ffff
The contents of W are XORed with
the 8-bit literal ‘k’. The result is placed
in W.
Description:
If ‘f’ = 0, the next instruction fetched
during the current instruction execution
is discarded and a NOPis executed,
making this a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
Words:
1
1
Cycles:
Q Cycle Activity:
Q1
Decode
Q2
Read
literal ‘k’
Q3
Process
Data
Q4
Write to W
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 19.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Example:
XORLW
0AFh
Before Instruction
W
=
B5h
1Ah
Words:
Cycles:
1
After Instruction
1(2)
W
=
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
No
operation
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
Example:
HERE
NZERO
ZERO
TSTFSZ CNT, 1
:
:
Before Instruction
PC
=
Address (HERE)
After Instruction
If CNT
PC
If CNT
PC
=
=
≠
=
00h,
Address (ZERO)
00h,
Address (NZERO)
© 2006 Microchip Technology Inc.
Advance Information
DS39760A-page 251
MICROCHIP [ MICROCHIP ]
