What is the problem?

[No_Fear]

Hi,
I wrote a code and it worked well(related with adc).Now i upgraded my code for 16 bit adc and it behaves weird.

#include <16F877A.h>
#include <string.h>
#use delay(clock=4000000)
#fuses XT, NOWDT, NOPROTECT, BROWNOUT, PUT, NOLVP
#use rs232(baud=9600,xmit=PIN_C6,rcv=PIN_C7)


void main() {

int v1;
char ON;

setup_adc_ports(ALL_ANALOG);
setup_adc(ADC_CLOCK_INTERNAL);
setup_psp(PSP_DISABLED);
setup_spi(FALSE);
setup_counters(RTCC_INTERNAL,RTCC_DIV_2);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_comparator(NC_NC_NC_NC);
setup_vref(FALSE);
set_tris_d(0x00);
ON = 1;

while (1)
{

delay_ms(500);

set_adc_channel( 0 );delay_us(50);v1 = read_adc();delay_us(50);
printf("Value:\%2X!",v1);

if (ON == 1) {output_high(PIN_D2);ON = 0;} else {output_low(PIN_D2);ON = 1;}

v1=0;
}

}
This works fine but when i load this, sometimes adc results shows different values than zero when no voltage on pin.When no voltage, it gives 64-128-96 (integer values). What is wrong? / Should i research fault in my circuit?

#include <16F877A.h>
#device adc=16 // !!! I Added tihs
#include <string.h>
#use delay(clock=4000000)
#fuses XT, NOWDT, PROTECT, BROWNOUT, PUT, NOLVP
#use rs232(baud=9600,xmit=PIN_C6,rcv=PIN_C7)


void main() {

int16 v1;
char ON;

setup_adc_ports(ALL_ANALOG);
setup_adc(ADC_CLOCK_INTERNAL);
setup_psp(PSP_DISABLED);
setup_spi(FALSE);
setup_counters(RTCC_INTERNAL,RTCC_DIV_2);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_comparator(NC_NC_NC_NC);
setup_vref(FALSE);
set_tris_d(0x00);
ON = 1;

while (1)
{

delay_ms(500);

set_adc_channel( 0 );delay_us(50);v1 = read_adc();delay_us(50);

printf("Value:\%4X!",v1);

if (ON == 1) {output_high(PIN_D2);ON = 0;} else {output_low(PIN_D2);ON = 1;}

v1=0;
}

}
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515488

[PCM programmer]

:=Hi,
:=I wrote a code and it worked well(related with adc).Now i upgraded my code for 16 bit adc and it behaves weird.
:=
---------------------------------------------------------
It's behaving pretty much according to the chart in the
CCS manual, in the read_adc() section. (Page 130 of the
manual, or page 142 in the Acrobat reader).

If you take a chip with a 10-bit ADC and set it for 16-bit
mode, CCS will left-justify the result. You don't like that,
so you need to set the compiler for 10-bit mode, which will
right-justify the result.

Remove this line:
#device adc=16

Use this line instead:
#device adc=10
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515491

[No_Fear]

Hmm, I can understand now.Thank you very much for your help

No_Fear


:=:=Hi,
:=:=I wrote a code and it worked well(related with adc).Now i upgraded my code for 16 bit adc and it behaves weird.
:=:=
:=---------------------------------------------------------
:=It's behaving pretty much according to the chart in the
:=CCS manual, in the read_adc() section. (Page 130 of the
:=manual, or page 142 in the Acrobat reader).
:=
:=If you take a chip with a 10-bit ADC and set it for 16-bit
:=mode, CCS will left-justify the result. You don't like that,
:=so you need to set the compiler for 10-bit mode, which will
:=right-justify the result.
:=
:=Remove this line:
:=#device adc=16
:=
:=Use this line instead:
:=#device adc=10
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515507