PIC12F635/PIC16F636/639
REGISTER 4-1:
PORTA: PORTA REGISTER
U-0
—
U-0
—
R/W-x
RA5
R/W-x
RA4
R-x
R/W-x
RA2
R/W-x
RA1
R/W-x
RA0
RA3
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’
RA<5:0>: PORTA I/O Pin bit
1= Port pin is > VIH
0= Port pin is < VIL
REGISTER 4-2:
TRISA: PORTA TRI-STATE REGISTER
U-0
—
U-0
—
R/W-1
R/W-1
R-1
R/W-1
R/W-1
R/W-1
TRISA5
TRISA4
TRISA3
TRISA2
TRISA1
TRISA0
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’
TRISA<5:0>: PORTA Tri-State Control bits
1= PORTA pin configured as an input (tri-stated)
0= PORTA pin configured as an output
Note 1: TRISA<3> always reads ‘1’.
2: TRISA<5:4> always reads ‘1’ in XT, HS and LP Oscillator modes.
DS41232D-page 48
© 2007 Microchip Technology Inc.