Datasheet

 1996 Microchip Technology Inc. DS30430B-page 65
PIC16F8X
SUBLW Subtract W from Literal
Syntax: [
label ] SUBLW k
Operands: 0 ≤ k ≤ 255
Operation: k – (W) → (W)
Status Affected: C, DC, Z
Encoding: 11 110x kkkk kkkk
Description: The W register is subtracted (2’s
complement method) from the
eight bit literal 'k'. The result is
placed in the W register.
Words: 1
Cycles: 1
Example 1: SUBLW 0x02
Before Instruction
W=1
C=?
After Instruction
W=1
C = 1; result is positive
Example 2: Before Instruction
W=2
C=?
After Instruction
W=0
C = 1; result is zero
Example 3: Before Instruction
W=3
C=?
After Instruction
W=FF
C = 0; result is negative
SUBWF Subtract W from f
Syntax: [
label ] SUBWF f,d
Operands: 0 ≤ f ≤ 127
d ∈ [0,1]
Operation: (f) – (W) → (dest)
Status Affected: C, DC, Z
Encoding: 00 0010 dfff ffff
Description: Subtract (2’s complement meth-
odize W register from register 'f'.
If 'd' is 0 the result is stored in
the W register. If 'd' is 1 the
result is stored back in register
'f'.
Words: 1
Cycles: 1
Example 1: SUBWF REG1,1
Before Instruction
REG1 = 3
W=2
C=?
After Instruction
REG1 = 1
W=2
C = 1; result is positive
Example 2: Before Instruction
REG1 = 2
W=2
C=?
After Instruction
REG1 = 0
W=2
C = 1; result is zero
Example 3: Before Instruction
REG1 = 1
W=2
C=?
After Instruction
REG1 = FF
W=2
C = 0; result is negative