English
Language : 

PIC18F1220_07 Datasheet, PDF (80/308 Pages) Microchip Technology – 18/20/28-Pin High-Performance, Enhanced Flash Microcontrollers with 10-bit A/D and nanoWatt Technology
PIC18F1220/1320
9.2 PIR Registers
The PIR registers contain the individual flag bits for the
peripheral interrupts. Due to the number of peripheral
interrupt sources, there are two Peripheral Interrupt
Request (Flag) registers (PIR1, PIR2).
Note 1: Interrupt flag bits are set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit or the Global
Interrupt Enable bit, GIE (INTCON<7>).
2: User software should ensure the appropri-
ate interrupt flag bits are cleared prior to
enabling an interrupt and after servicing
that interrupt.
REGISTER 9-4:
PIR1: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 1
U-0
R/W-0
R-0
R-0
U-0
R/W-0 R/W-0
—
ADIF
RCIF
TXIF
—
CCP1IF TMR2IF
bit 7
R/W-0
TMR1IF
bit 0
bit 7 Unimplemented: Read as ‘0’
bit 6 ADIF: A/D Converter Interrupt Flag bit
1 = An A/D conversion completed (must be cleared in software)
0 = The A/D conversion is not complete
bit 5 RCIF: EUSART Receive Interrupt Flag bit
1 = The EUSART receive buffer, RCREG, is full (cleared when RCREG is read)
0 = The EUSART receive buffer is empty
bit 4 TXIF: EUSART Transmit Interrupt Flag bit
1 = The EUSART transmit buffer, TXREG, is empty (cleared when TXREG is written)
0 = The EUSART transmit buffer is full
bit 3 Unimplemented: Read as ‘0’
bit 2 CCP1IF: CCP1 Interrupt Flag bit
Capture mode:
1 = A TMR1 register capture occurred (must be cleared in software)
0 = No TMR1 register capture occurred
Compare mode:
1 = A TMR1 register compare match occurred (must be cleared in software)
0 = No TMR1 register compare match occurred
PWM mode:
Unused in this mode.
bit 1 TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
1 = TMR2 to PR2 match occurred (must be cleared in software)
0 = No TMR2 to PR2 match occurred
bit 0 TMR1IF: TMR1 Overflow Interrupt Flag bit
1 = TMR1 register overflowed (must be cleared in software)
0 = TMR1 register did not overflow
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
DS39605F-page 78
© 2007 Microchip Technology Inc.