PIC16F631/677/685/687/689/690
REGISTER 4-5:
WPUA: PORTA REGISTER
U-0
—
U-0
—
R/W-1
R/W-1
U-0
—
R/W-1
R/W-1
R/W-1
WPUA5
WPUA4
WPUA2
WPUA1
WPUA0
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 7-6
bit 5-4
Unimplemented: Read as ‘0’
WPUA<5:4>: Weak Pull-up Register bit
1= Pull-up enabled
0= Pull-up disabled
bit 3
Unimplemented: Read as ‘0’
bit 2-0
WPUA<2:0>: Weak Pull-up Register bit
1= Pull-up enabled
0= Pull-up disabled
Note 1: Global RABPU bit of the OPTION register must be enabled for individual pull-ups to be enabled.
2: The weak pull-up device is automatically disabled if the pin is in Output mode (TRISA = 0).
3: The RA3 pull-up is enabled when configured as MCLR and disabled as an I/O in the Configuration Word.
4: WPUA<5:4> always reads ‘1’ in XT, HS and LP Oscillator modes.
REGISTER 4-6:
IOCA: INTERRUPT-ON-CHANGE PORTA REGISTER
U-0
—
U-0
—
R/W-0
IOCA5
R/W-0
IOCA4
R/W-0
IOCA3
R/W-0
IOCA2
R/W-0
IOCA1
R/W-0
IOCA0
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 7-6
bit 5-0
Unimplemented: Read as ‘0’
IOCA<5:0>: Interrupt-on-change PORTA Control bit
1= Interrupt-on-change enabled
0= Interrupt-on-change disabled
Note 1: Global Interrupt Enable (GIE) must be enabled for individual interrupts to be recognized.
2: IOCA<5:4> always reads ‘1’ in XT, HS and LP Oscillator modes.
DS41262D-page 62
© 2007 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
