PIC18F2480 MICROCHIP [Microchip Technology], PIC18F2480 Datasheet - Page 281

• Manufacturer Part Number: PIC18F2480
• Description: 28/40/44-Pin Enhanced Flash Microcontrollers with ECAN Technology, 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

EXAMPLE 23-2:
 2004 Microchip Technology Inc.
ErrorInterrupt
TXB2Interrupt
TXB1Interrupt
TXB0Interrupt
RXB1Interrupt
RXB0Interrupt
AccessBuffer
BCF
…
RETFIE
BCF
GOTO
BCF
GOTO
BCF
GOTO
BCF
GOTO
BCF
GOTO
; Copy CANSTAT.ICODE bits to CANCON.WIN bits
MOVF
ANDLW
MOVWF
MOVF
ANDLW
IORWF
MOVFF
; Access current buffer…
; User code
; Restore CANCON.WIN bits
MOVF
ANDLW
IORWF
; Do not need to restore CANSTAT - it is read-only register.
; Return from interrupt or check for another module interrupt source
PIR3, ERRIF
PIR3, TXB2IF
AccessBuffer
PIR3, TXB1IF
AccessBuffer
PIR3, TXB0IF
AccessBuffer
PIR3, RXB1IF
Accessbuffer
PIR3, RXB0IF
AccessBuffer
TempCANCON, W
B’11110001’
TempCANCON
TempCANSTAT, W
B’00001110’
TempCANCON
TempCANCON, CANCON
CANCON, W
B’11110001’
TempCANCON
WIN AND ICODE BITS USAGE IN INTERRUPT SERVICE ROUTINE TO ACCESS
TX/RX BUFFERS (CONTINUED)
PIC18F2480/2580/4480/4580
Preliminary
; Clear the interrupt flag
; Handle error.
; Clear the interrupt flag
; Clear the interrupt flag
; Clear the interrupt flag
; Clear the interrupt flag
; Clear the interrupt flag
; This is either TX or RX interrupt
; Clear CANCON.WIN bits before copying
; new ones.
; Use previously saved CANCON value to
; make sure same value.
; Copy masked value back to TempCANCON
; Retrieve ICODE bits
; Use previously saved CANSTAT value
; to make sure same value.
; Copy ICODE bits to WIN bits.
; Copy the result to actual CANCON
; Preserve current non WIN bits
; Restore original WIN bits
DS39637A-page 279