PIC16F627A Datasheet, PDF (123/168 Pages) Microchip Technology – FLASH-Based 8-Bit CMOS Microcontrollers

PIC16F627A/628A/648A
RETLW
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example
TABLE
Return with Literal in W
[ label ] RETLW k
0 ≤ k ≤ 255
k → (W);
TOS → PC
None
11
01xx kkkk kkkk
The W register is loaded with
the eight bit literal 'k'. The pro-
gram counter is loaded from the
top of the stack (the return
address). This is a two-cycle
instruction.
1
2
CALL TABLE;W contains table
;offset value
• ;W now has table value
•
•
ADDWF PC;W = offset
RETLW k1;Begin table
RETLW k2;
•
•
•
RETLW kn; End of table
Before Instruction
W = 0x07
After Instruction
W = value of k8
RETURN
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example
Return from Subroutine
[ label ] RETURN
None
TOS → PC
None
00
0000 0000 1000
Return from subroutine. The
stack is POPed and the top of
the stack (TOS) is loaded into
the program counter. This is a
two-cycle instruction.
1
2
RETURN
After Interrupt
PC = TOS
RLF
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Rotate Left f through Carry
[ label ] RLF f,d
0 ≤ f ≤ 127
d ∈ [0,1]
See description below
C
00
1101 dfff ffff
The contents of register 'f' are
rotated one bit to the left through
the Carry Flag. If 'd' is 0 the result
is placed in the W register. If 'd' is
1 the result is stored back in reg-
ister 'f'.
C
REGISTER F
Words:
Cycles:
Example
1
1
RLF
REG1, 0
Before Instruction
REG1=1110 0110
C =0
After Instruction
REG1=1110 0110
W = 1100 1100
C =1
 2002 Microchip Technology Inc.
Preliminary
DS40044A-page 121