S3F84B8_UM_REV 1.00
13 A/D CONVERTER
13-6
Example 13-1 Configuring A/D Converter
;-----------------<< Interrupt Vector Address >>
VECTOR F0H, INT_ADC
;
;--------------<< Smart Option >>
ORG
003CH
DB
0FFH
; 003CH, must be initialized to 1
DB
0FFH
; 003DH, must be initialized to 1
DB
0FFH
; 003EH, must be initialized to 1
DB
0FFH
; 003FH, disables LVR and internal RC oscillator
ORG
0100H
RESET:
DI
;
Disables
interrupt
LD
BTCON,#10100011B
;
Disables
Watchdog
LD
P2CONH,#11111111B
;
Configures P2.4–P2.7 AD input
LD
P2CONL,#11111111B ; Configures P2.0–P2.3 AD input
EI
;
Enables
interrupt
;--------------<< Main loop >>
MAIN:
JR
t,
MAIN
AD_CONV: LD ADCON,
#00110001B ; Selects analog input channel
P2.1
;
Enables
ADC
interrupt
;
Selects
conversion
speed
f
OSC
/8
;
Sets
conversion
start
bit
NOP
; If you set conversion speed to f
OSC
/8
; at least one NOP must be included
INT_ADC:
LD
R2,
ADDATAH
;
LD
R3,
ADDATAL
;
AND
ADCON, #11110111B ; Clears pending bit
;
IRET
;
END