PIC18F2480 MICROCHIP [Microchip Technology], PIC18F2480 Datasheet - Page 260

• Manufacturer Part Number: PIC18F2480
• Description: 28/40/44-Pin Enhanced Flash Microcontrollers with ECAN Technology, 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2480/2580/4480/4580
20.1
There are eight modes of operation for the compara-
tors, shown in Figure 20-1. Bits CM2:CM0 of the
CMCON register are used to select these modes. The
TRISA register controls the data direction of the com-
parator pins for each mode. If the Comparator mode is
FIGURE 20-1:
DS39637A-page 258
Comparators Reset (POR Default Value)
CM2:CM0 = 000
Two Independent Comparators
CM2:CM0 = 010
Two Common Reference Comparators
CM2:CM0 = 100
One Independent Comparator with Output
CM2:CM0 = 001
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
A = Analog Input, port reads zeros always
* Setting the TRISA<5:4> bits will disable the comparator outputs by configuring the pins as inputs.
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RE1/WR/AN6/C1OUT*
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
Comparator Configuration
A
A
A
D
A
A
A
A
A
A
A
A
COMPARATOR I/O OPERATING MODES
A
A
D
D
V
V
V
V
V
V
V
V
V
V
V
V
IN
IN
IN
IN
V
V
V
V
IN
IN
IN
IN
IN
IN
IN
IN
-
+
-
+
IN
IN
IN
IN
-
+
-
+
-
+
-
+
-
+
-
+
C1
C2
C1
C2
C1
C2
C1
C2
C1OUT
C2OUT
D = Digital Input
Off
Off
(Read as ‘0’)
C1OUT
C2OUT
(Read as ‘0’)
C1OUT
Off
(Read as ‘0’)
Preliminary
Two Common Reference Comparators with Outputs
CM2:CM0 = 101
Two Independent Comparators with Outputs
CM2:CM0 = 011
Comparators Off
CM2:CM0 = 111
Four Inputs Multiplexed to Two Comparators
CM2:CM0 = 110
RD1/PSP1/
C1IN-
RD0/PSP0/
C1IN+
RD3/PSP3/
C2IN-
RD2/PSP2/
C2IN+
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RE1/WR/AN6/C1OUT*
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
RE2/CS/AN7/C2OUT*
RD1/PSP1/C1IN-
RD0/PSP0/C1IN+
RE1/WR/AN6/C1OUT*
RD3/PSP3/C2IN-
RD2/PSP2/C2IN+
RE2/CS/AN7/C2OUT*
changed, the comparator output level may not be valid
for the specified mode change delay shown in
Section 27.0 “Electrical Characteristics”.
Note:
CIS (CMCON<3>) is the Comparator Input Switch
A
A
A
A
Comparator interrupts should be disabled
during a Comparator mode change;
otherwise, a false interrupt may occur.
CIS = 0
CIS = 1
CIS = 0
CIS = 1
A
A
A
D
A
A
A
A
D
D
D
D
 2004 Microchip Technology Inc.
V
V
V
V
V
V
V
V
V
V
V
V
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
IN
-
+
-
+
-
+
-
+
V
V
V
V
-
+
-
+
IN
IN
IN
IN
CV
-
+
-
+
C1
C2
C1
C2
C1
C2
REF
C1
C2
From V
C1OUT
C2OUT
C1OUT
C2OUT
Off
(Read as ‘0’)
Off
(Read as ‘0’)
REF
C1OUT
C2OUT
Module