PIC16F688
2.2.2.5
PIR1 Register
The PIR1 register contains the interrupt flag bits, as
shown in Register 2-5.
Note:
Interrupt flag bits are set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit or the global
enable bit, GIE bit of the INTCON register.
User software should ensure the appropri-
ate interrupt flag bits are clear prior to
enabling an interrupt.
REGISTER 2-5:
PIR1: PERIPHERAL INTERRUPT REQUEST REGISTER 1
R/W-0
EEIF
R/W-0
ADIF
R-0
R/W-0
C2IF
R/W-0
C1IF
R/W-0
OSFIF
R-0
R/W-0
RCIF
TXIF
TMR1IF
bit 7
bit 0
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
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
EEIF: EEPROM Write Operation Interrupt Flag bit
1= The write operation completed (must be cleared in software)
0= The write operation has not completed or has not been started
ADIF: A/D Converter Interrupt Flag bit
1= A/D conversion complete (must be cleared in software)
0= A/D conversion has not completed or has not been started
RCIF: EUSART Receive Interrupt Flag bit
1= The EUSART receive buffer is full (cleared by reading RCREG)
0= The EUSART receive buffer is not full
C2IF: Comparator C2 Interrupt Flag bit
1= Comparator output (C2OUT bit) has changed (must be cleared in software)
0= Comparator output (C2OUT bit) has not changed
C1IF: Comparator C1 Interrupt Flag bit
1= Comparator output (C1OUT bit) has changed (must be cleared in software)
0= Comparator output (C1OUT bit) has not changed
OSFIF: Oscillator Fail Interrupt Flag bit
1= System oscillator failed, clock input has changed to INTOSC (must be cleared in software)
0= System clock operating
TXIF: EUSART Transmit Interrupt Flag bit
1= The EUSART transmit buffer is empty (cleared by writing to TXREG)
0= The EUSART transmit buffer is full
TMR1IF: Timer1 Overflow Interrupt Flag bit
1= The TMR1 register overflowed (must be cleared in software)
0= The TMR1 register did not overflow
© 2007 Microchip Technology Inc.
DS41203D-page 17
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