PIC16F87XA
REGISTER 11-2: ADCON1 REGISTER (ADDRESS 9Fh)
R/W-0
ADFM
R/W-0
U-0
—
U-0
—
R/W-0
R/W-0
R/W-0
R/W-0
PCFG0
bit 0
ADCS2
PCFG3
PCFG2
PCFG1
bit 7
bit 7
bit 6
ADFM: A/D Result Format Select.bit
1= Right justified. Six (6) Most Significant bits of ADRESH are read as ’0’.
0= Left justified. Six (6) Least Significant bits of ADRESL are read as ’0’.
ADCS2: A/D Conversion Clock Select bit (ADCON1 bits in shaded area and in bold)
ADCON1
<ADCS2> <ADCS1:ADCS0>
ADCON0
Clock Conversion
0
0
0
0
1
1
1
1
00
01
10
11
00
01
10
11
FOSC/2
FOSC/8
FOSC/32
FRC (clock derived from the internal A/D RC oscillator)
FOSC/4
FOSC/16
FOSC/64
FRC (clock derived from the internal A/D RC oscillator)
bit 5-4
bit 3-0
Unimplemented: Read as '0'
PCFG3:PCFG0: A/D Port Configuration Control bits
PCFG
<3:0>
AN7 AN6 AN5 AN4
AN3
AN2
AN1 AN0 VREF+ VREF- C / R
0000
0001
0010
0011
0100
0101
011x
1000
1001
1010
1011
1100
1101
1110
1111
A
A
D
D
D
D
D
A
D
D
D
D
D
D
D
A
A
D
D
D
D
D
A
D
D
D
D
D
D
D
A
A
D
D
D
D
D
A
A
A
A
D
D
D
D
A
A
A
A
D
D
D
A
A
A
A
A
D
D
D
A
VREF+
A
A
A
A
A
D
D
D
A
A
A
A
A
A
D
A
A
A
A
A
A
D
D
A
A
A
A
A
A
D
A
A
A
A
A
A
A
A
VDD
AN3
VDD
AN3
VDD
AN3
—
VSS
VSS
VSS
VSS
VSS
VSS
—
8 / 0
7 / 1
5 / 0
4 / 1
3 / 0
2 / 1
0 / 0
6 / 2
6 / 0
5 / 1
4 / 2
3 / 2
2 / 2
1 / 0
1 / 2
VREF+
A
VREF+
D
VREF+ VREF-
AN3
VDD
AN3
AN3
AN3
AN3
VDD
AN3
AN2
VSS
VSS
AN2
AN2
AN2
VSS
AN2
A
A
A
VREF+
VREF+ VREF-
VREF+ VREF-
VREF+ VREF-
D
D
VREF+ VREF-
A = Analog input D = Digital I/O
C / R = # of analog input channels / # of A/D voltage references
Legend:
R = Readable bit
W = Writable bit
’1’ = Bit is set
U = Unimplemented bit, read as ‘0’
’0’ = Bit is cleared x = Bit is unknown
- n = Value at POR reset
Note: On any device RESET, the port pins that are multiplexed with analog functions (ANx)
are forced to be an analog input.
DS39582A-page 126
AdvanceInformation
2001 Microchip Technology Inc.