PIC16F62X
The CMCON register, shown in Register 9-1, controls
the comparator input and output multiplexers. A block
diagram of the comparator is shown in Figure 9-1.
9.0
COMPARATOR MODULE
The comparator module contains two analog
comparators. The inputs to the comparators are
multiplexed with the RA0 through RA3 pins. The
on-chip Voltage Reference (Section 11.0) can also be
an input to the comparators.
REGISTER 9-1: CMCON REGISTER (ADDRESS 01Fh)
R-0
R-0
R/W-0
R/W-0
R/W-0
R/W-0
CM2
R/W-0
CM1
R/W-0
CM0
bit0
C2OUT C1OUT C2INV C1INV CIS
R = Readable bit
W = Writable bit
U = Unimplemented bit, read
as ’0’
bit7
-n = Value at POR reset
bit 7:
C2OUT: Comparator 2 output
When C2INV=0;
1= C2 VIN+ > C2 VIN–
0= C2 VIN+ < C2 VIN–
When C2INV=1;
0= C2 VIN+ > C2 VIN–
1= C2 VIN+ < C2 VIN–
bit 6:
C1OUT: Comparator 1 output
When C1INV=0;
1= C1 VIN+ > C1 VIN–
0= C1 VIN+ < C1 VIN–
When C1INV=1;
0= C1 VIN+ > C1 VIN–
1= C1 VIN+ < C1 VIN–
bit 5:
bit 4:
bit 3:
C2INV: Comparator 2 output inversion
1= C2 Output inverted
0= C2 Output not inverted
C1INV: Comparator 1 output inversion
1= C1 Output inverted
0= C1 Output not inverted
CIS: Comparator Input Switch
When CM2:CM0: = 001:
Then:
1= C1 VIN– connects to RA3
0= C1 VIN– connects to RA0
When CM2:CM0 = 010:
Then:
1= C1 VIN– connects to RA3
C2 VIN– connects to RA2
0= C1 VIN– connects to RA0
C2 VIN– connects to RA1
bit 2-0: CM2:CM0: Comparator mode
Figure 9-1 shows the comparator modes and CM2:CM0 bit settings.
1999 Microchip Technology Inc.
Preliminary
DS40300B-page 57