PIC16F883 Microchip Technology Inc., PIC16F883 Datasheet - Page 105

• Manufacturer Part Number: PIC16F883
• Description: 28/40/44-pin Flash-based, 8-bit Cmos Microcontrollers With Nanowatt Technology
• Manufacturer: Microchip Technology Inc.

9.2.6
This is an example procedure for using the ADC to
perform an Analog-to-Digital conversion:
1.
2.
3.
4.
5.
6.
7.
8.
© 2007 Microchip Technology Inc.
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
• 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: See
A/D CONVERSION PROCEDURE
user is attempting to wake-up from Sleep
and resume in-line code execution.
Requirements”.
Section 9.3
(1)
“A/D
(2)
.
Acquisition
PIC16F882/883/884/886/887
Preliminary
EXAMPLE 9-1:
;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.
;
BANKSEL
MOVLW
MOVWF
BANKSEL
BSF
BANKSEL
BSF
BANKSEL
MOVLW
MOVWF
CALL
BSF
BTFSC
GOTO
BANKSEL
MOVF
MOVWF
BANKSEL
MOVF
MOVWF
ADCON1
B’10000000’ ;right justify
ADCON1
TRISA
TRISA,0
ANSEL
ANSEL,0
ADCON0
B’11000001’ ;ADC Frc clock,
ADCON0
SampleTime
ADCON0,GO
ADCON0,GO
$-1
ADRESH
ADRESH,W
RESULTHI
ADRESL
ADRESL,W
RESULTLO
A/D CONVERSION
;
;Vdd and Vss as Vref
;
;Set RA0 to input
;
;Set RA0 to analog
;
;AN0, On
;Acquisiton delay
;Start conversion
;Is conversion done?
;No, test again
;
;Read upper 2 bits
;store in GPR space
;
;Read lower 8 bits
;Store in GPR space
DS41291D-page 103