Datasheet

Table Of Contents
PIC16F631/677/685/687/689/690
DS41262E-page 106 © 2008 Microchip Technology Inc.
TABLE 8-2: SUMMARY OF REGISTERS ASSOCIATED WITH THE COMPARATOR AND VOLTAGE
REFERENCE MODULES
REGISTER 8-5: VRCON: VOLTAGE REFERENCE CONTROL REGISTER
R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
C1VREN C2VREN VRR VP6EN VR3 VR2 VR1 VR0
bit 7 bit 0
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
bit 7 C1VREN: Comparator 1 Voltage Reference Enable bit
1 = CV
REF circuit powered on and routed to C1VREF input of Comparator C1
0 = 0.6 Volt constant reference routed to C1V
REF input of Comparator C1
bit 6 C2VREN: Comparator 2 Voltage Reference Enable bit
1 = CVREF circuit powered on and routed to C2VREF input of Comparator C2
0 = 0.6 Volt constant reference routed to C2V
REF input of Comparator C2
bit 5 VRR: CVREF Range Selection bit
1 = Low range
0 = High range
bit 4 VP6EN: 0.6V Reference Enable bit
1 = Enabled
0 = Disabled
bit 3-0 VR<3:0>: Comparator Voltage Reference CVREF Value Selection bits (0 VR<3:0> 15)
When VRR = 1: CVREF = (VR<3:0>/24) * VDD
When VRR = 0: CVREF = VDD/4 + (VR<3:0>/32) * VDD
Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Value on
POR, BOR
Value on
all other
Resets
ANSEL ANS7 ANS6 ANS5 ANS4
ANS3 ANS2 ANS1 ANS0 1111 1111 1111 1111
CM1CON0 C1ON C1OUT
C1OE C1POL C1R C1CH1 C1CH0 0000 -000 0000 0000
CM2CON0 C2ON C2OUT
C2OE C2POL C2R C2CH1 C2CH0 0000 -000 0000 -000
CM2CON1 MC1OUT MC2OUT
T1GSS C2SYNC 00-- --10 00-- --10
INTCON GIE PEIE
T0IE INTE RABIE T0IF INTF RABIF 0000 000x 0000 000x
PIE2 OSFIE C2IE C1IE EEIE
0000 ---- 0000 ----
PIR2 OSFIF C2IF C1IF EEIF
0000---- 0000----
PORTA
RA5 RA4 RA3 RA2 RA1 RA0 --xx xxxx --uu uuuu
PORTC
RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0 xxxx xxxx uuuu uuuu
SRCON SR1 SR0 C1SEN C2REN PULSS PULSR
0000 00-- 0000 00--
TRISA
TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 --11 1111 --11 1111
TRISC
TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 1111 1111 1111 1111
VRCON C1VREN C2VREN VRR VP6EN VR3 VR2 VR1 VR0 0000 0000 0000 0000
Legend: x = unknown, u = unchanged, – = unimplemented, read as ‘0’. Shaded cells are not used for comparator.