Datasheet

PIC16F785/HV785
DS41249E-page 72 © 2008 Microchip Technology Inc.
REGISTER 10-1: VRCON: VOLTAGE REFERENCE CONTROL REGISTER
R/W-0 R/W-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0
C1VREN
(1)
C2VREN
(1)
VRR —VR3VR2VR1VR0
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)
1 = CVREF circuit powered on and routed to C1VREF input of comparator 1
0 = 1.2 Volt VR routed to C1V
REF input of comparator 1
bit 6 C2VREN: Comparator 2 Voltage Reference Enable bit
(1)
1 = CVREF circuit powered on and routed to C2VREF input of comparator 2
0 = 1.2 Volt VR routed to C2V
REF input of comparator 2
bit 5 VRR: Comparator Voltage Reference CV
REF Range Selection bit
1 = Low Range
0 = High Range
bit 4 Unimplemented: Read as ‘0’
bit 3-0 VR<3:0>: Comparator Voltage Reference CV
REF Value Selection 0 ≤ VR<3:0> ≤ 15
When VRR = 1 and CVREN = 1: CVREF = (VR<3:0> x VDD/24)
When VRR = 0 and CVREN = 1: CV
REF = (VDD/4) + (VR<3:0> x VDD/32)
When CxVREN = 0 and VREN = 1: CxV
REF = 1.2V from VR module
Note 1: When C1VREN, C2VREN and CVROE (Register 10-2) are all low, the CVREF circuit is powered down and
does not contribute to I
DD current.