PIC16F872
2.2.2.5
PIR1 REGISTER
Note: Interrupt flag bits get set when an interrupt
condition occurs, regardless of the state of
its corresponding enable bit or the global
enable bit, GIE (INTCON<7>). User soft-
ware should ensure the appropriate inter-
rupt bits are clear prior to enabling an
interrupt.
The PIR1 register contains the individual flag bits for
the peripheral interrupts.
REGISTER 2-5: PIR1 REGISTER (ADDRESS 0Ch)
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
—
ADIF
—
—
SSPIF
CCP1IF TMR2IF TMR1IF
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as ‘0’
bit7
- n= Value at POR reset
bit 7:
bit 6:
Reserved: Always maintain this bit clear
ADIF: A/D Converter Interrupt Flag bit
1= An A/D conversion completed
0= The A/D conversion is not complete
bit 5-4: Reserved: Always maintain this bit clear
bit 3: SSPIF: Synchronous Serial Port (SSP) Interrupt Flag
1= The SSP interrupt condition has occurred, and must be cleared in software before returning from the
interrupt service routine. The conditions that will set this bit are:
SPI
A transmission/reception has taken place.
I2C Slave
A transmission/reception has taken place.
I2C Master
A transmission/reception has taken place.
The initiated start condition was completed by the SSP module.
The initiated stop condition was completed by the SSP module.
The initiated restart condition was completed by the SSP module.
The initiated acknowledge condition was completed by the SSP module.
A start condition occurred while the SSP module was idle (Multimaster system).
A stop condition occurred while the SSP module was idle (Multimaster system).
0= No SSP interrupt condition has occurred.
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:
bit 0:
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
TMR1IF: TMR1 Overflow Interrupt Flag bit
1= TMR1 register overflowed (must be cleared in software)
0= TMR1 register did not overflow
DS30221A-page 16
Preliminary
1999 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
