PIC18F23K20-E/MLQTP MICROCHIP [Microchip Technology], PIC18F23K20-E/MLQTP Datasheet - Page 262

• Manufacturer Part Number: PIC18F23K20-E/MLQTP
• Description: 28/40/44-Pin Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2XK20/4XK20
19.2.9
This is an example procedure for using the ADC to
perform an Analog-to-Digital conversion:
1.
2.
3.
4.
5.
6.
7.
8.
DS41303B-page 260
Note 1: The global interrupt can be disabled if the
Configure Port:
• Disable pin output driver (See TRIS register)
• Configure pin as analog
Configure the ADC module:
• Select ADC conversion clock
• Configure voltage reference
• Select ADC input channel
• Select result format
• Select acquisition delay
• Turn on ADC module
Configure ADC interrupt (optional):
• Clear ADC interrupt flag
• Enable ADC interrupt
• Enable peripheral interrupt
• Enable global interrupt
Wait the required acquisition time
Start conversion by setting the GO/DONE bit.
Wait for ADC conversion to complete by one of
the following:
• Polling the GO/DONE bit
• Waiting for the ADC interrupt (interrupts
Read ADC Result
Clear the ADC interrupt flag (required if interrupt
is enabled).
enabled)
2: Software delay required if ACQT bits are
A/D CONVERSION PROCEDURE
user is attempting to wake-up from Sleep
and resume in-line code execution.
set to zero delay. See Section 19.3 “A/D
Acquisition Requirements”.
(1)
(2)
.
Advance Information
EXAMPLE 19-1:
;This code block configures the ADC
;for polling, Vdd and Vss as reference, Frc
clock and AN0 input.
;
;Conversion start & polling for completion
; are included.
;
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
MOVLW
MOVWF
BSF
ADCPoll:
BTFSC
BRA
; Result is complete - store 2 MSbits in
; RESULTHI and 8 LSbits in RESULTLO
MOVFF
MOVFF
B’10101111’ ;right justify, Frc,
ADCON2
B’00000000’ ;ADC ref = Vdd,Vss
ADCON1
TRISA,0
ANSEL,0
B’00000001’ ;AN0, ADC on
ADCON0
ADCON0,GO
ADCON0,GO
ADCPoll
ADRESH,RESULTHI
ADRESL,RESULTLO
A/D CONVERSION
© 2007 Microchip Technology Inc.
; & 12 TAD ACQ time
;
;Set RA0 to input
;Set RA0 to analog
;
;Start conversion
;Is conversion done?
;No, test again