PIC16F87XA
TABLE 4-1:
Name
RA0/AN0
RA1/AN1
RA2/AN2/V
REF
-/CV
REF
RA3/AN3/V
REF
+
RA4/T0CKI/C1OUT
RA5/SS/AN4/C2OUT
PORTA FUNCTIONS
Bit#
bit0
bit1
bit2
bit3
bit4
bit5
Buffer
TTL
TTL
TTL
TTL
ST
TTL
Input/output or analog input.
Input/output or analog input.
Input/output or analog input or V
REF
- or CV
REF
.
Input/output or analog input or V
REF+.
Input/output or external clock input for Timer0 or comparator output.
Output is open drain type.
Input/output or slave select input for synchronous serial port or analog
input or comparator output.
Function
Legend: TTL = TTL input, ST = Schmitt Trigger input
TABLE 4-2:
Address
05h
85h
9Ch
9Dh
9Fh
Name
PORTA
TRISA
CMCON
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Bit 7
—
—
C2OUT
ADFM
Bit 6
—
—
C1OUT
ADCS2
Bit 5
RA5
C2INV
CVRR
—
Bit 4
RA4
C1INV
—
—
Bit 3
RA3
CIS
CVR3
PCFG3
Bit 2
RA2
CM2
CVR2
PCFG2
Bit 1
RA1
CM1
CVR1
PCFG1
Bit 0
RA0
CM0
CVR0
PCFG0
Value on:
POR,
BOR
--0x 0000
--11 1111
0000 0111
000- 0000
--0- 0000
Value on
all other
RESETS
--0u 0000
--11 1111
0000 0111
000- 0000
--0- 0000
PORTA Data Direction Register
CVRCON
ADCON1
CVREN CVROE
Legend:
x
= unknown,
u
= unchanged,
-
= unimplemented locations read as '0'. Shaded cells are not used by PORTA.
Note:
When using the SSP module in SPI Slave mode and SS enabled, the A/D converter must be set to one of
the following modes, where PCFG3:PCFG0 =
0100, 0101, 011x, 1101, 1110, 1111.
2001 Microchip Technology Inc.
Advance Information
DS39582A-page 41
MICROCHIP [ MICROCHIP TECHNOLOGY ]
