PIC18F2510-E/P MICROCHIP [Microchip Technology], PIC18F2510-E/P Datasheet - Page 288

• Manufacturer Part Number: PIC18F2510-E/P
• Description: 28/40/44-Pin Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2X1X/4X1X
RETFIE
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
DS39636D-page 290
Q Cycle Activity:
After Interrupt
operation
Decode
PC
W
BSR
STATUS
GIE/GIEH, PEIE/GIEL
No
Q1
operation
operation
Return from Interrupt
RETFIE {s}
s ∈ [0,1]
(TOS) → PC,
1 → GIE/GIEH or PEIE/GIEL,
if s = 1
(WS) → W,
(STATUSS) → STATUS,
(BSRS) → BSR,
PCLATU, PCLATH are unchanged.
GIE/GIEH, PEIE/GIEL.
Return from Interrupt. Stack is popped
and Top-of-Stack (TOS) is loaded into
the PC. Interrupts are enabled by
setting either the high or low priority
global interrupt enable bit. If ‘s’ = 1, the
contents of the shadow registers WS,
STATUSS and BSRS are loaded into
their corresponding registers, W,
STATUS and BSR. If ‘s’ = 0, no update
of these registers occurs (default).
1
2
RETFIE
0000
No
No
Q2
1
0000
operation
operation
=
=
=
=
=
No
No
Q3
TOS
WS
BSRS
STATUSS
1
0001
Set GIEH or
from stack
operation
POP PC
GIEL
No
Q4
000s
RETLW
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
TABLE
Q Cycle Activity:
:
:
:
CALL TABLE ; W contains table
ADDWF PCL
RETLW k0
RETLW k1
RETLW kn
Before Instruction
After Instruction
operation
Decode
W
W
No
Q1
; offset value
; W now has
; table value
; W = offset
; Begin table
;
; End of table
=
=
operation
Return Literal to W
RETLW k
0 ≤ k ≤ 255
k → W,
(TOS) → PC,
PCLATU, PCLATH are unchanged
None
W is loaded with the eight-bit literal ‘k’.
The program counter is loaded from the
top of the stack (the return address).
The high address latch (PCLATH)
remains unchanged.
1
2
literal ‘k’
Read
0000
No
Q2
07h
value of kn
© 2009 Microchip Technology Inc.
1100
operation
Process
Data
No
Q3
kkkk
from stack,
Write to W
operation
POP PC
No
Q4
kkkk