
2004 Microchip Technology Inc.
DS30491C-page 259
PIC18F6585/8585/6680/8680
20.0
COMPARATOR MODULE
The
comparator
module
contains
two
analog
comparators. The inputs to the comparators are
multiplexed with the RF1 through RF6 pins. The on-
the comparators.
the comparator input and output multiplexers. A block
diagram of the various comparator configurations is
REGISTER 20-1:
CMCON REGISTER
R-0
R/W-0
C2OUT
C1OUT
C2INV
C1INV
CIS
CM2
CM1
CM0
bit 7
bit 0
bit 7
C2OUT: Comparator 2 Output bit
When C2INV = 0:
1
= C2 VIN+ > C2 VIN-
0
= C2 VIN+ < C2 VIN-
When C2INV = 1:
1
= C2 VIN+ < C2 VIN-
0
= C2 VIN+ > C2 VIN-
bit 6
C1OUT: Comparator 1 Output bit
When C1INV = 0:
1
= C1 VIN+ > C1 VIN-
0
= C1 VIN+ < C1 VIN-
When C1INV = 1:
1
= C1 VIN+ < C1 VIN-
0
= C1 VIN+ > C1 VIN-
bit 5
C2INV: Comparator 2 Output Inversion bit
1
= C2 output inverted
0
= C2 output not inverted
bit 4
C1INV: Comparator 1 Output Inversion bit
1
= C1 output inverted
0
= C1 output not inverted
bit 3
CIS: Comparator Input Switch bit
When CM2:CM0 = 110:
1
=C1 VIN- connects to RF5/AN10
C2 VIN- connects to RF3/AN8
0
=C1 VIN- connects to RF6/AN11
C2 VIN- connects to RF4/AN9
bit 2-0
CM2:CM0: Comparator Mode bits
Figure 20-1 shows the Comparator modes and CM2:CM0 bit settings.
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
- n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown