multi analog channel on 16c771

[beaker]

using CCS compiler V2.707

Here is my short code that I am having trouble with, I need to sample two analog channels at 12 bit on the 16c771. For some reason, I cannot get the channel switching to work, a single channel of A0 works fine.
comments?

[/code]
*********************************************************************************************
*/



#include <16C771.h>

#use delay (Clock=4000000,restart_wdt)
#fuses HS,WDT,NOPROTECT
//#use fast_io(B)
SET_TRIS_B(0x81);

/*
*********************************************************************************************
* DEFINES
*********************************************************************************************
*/


#DEFINE pot_input PIN_A0 //sets analog input as pin A0
#DEFINE d_out PIN_B7 //sets digital output as pin B7
#DEFINE tx_enable PIN_B4 // was B6
#DEFINE tx_cts PIN_B2
#DEFINE grn_led_toggle PIN_B3
#DEFINE red_led_toggle PIN_B5
#DEFINE batt_input PIN_B0

#byte ADCON0=0x1F
#byte ADCON1=0x9F
#byte ADRESL=0x9E
#byte ADRESH=0x1E
#bit ADFM_BIT = ADCON1.7
#bit GO_BIT= ADCON0.2

#define BytePtr(var,offset) (char *)(&var + offset)

#USE RS232(BAUD=4800, XMIT=PIN_B7, RCV=PIN_B6, STREAM=USB) // serial connect


/*
*********************************************************************************************
* FUNCTIONS
*********************************************************************************************
*/

void init_hardware()
{
//Setup_adc_ports( 0x00 );
//setup_port_a( 0x00);
setup_adc(ADC_CLOCK_INTERNAL);
output_low(tx_enable); // turn off transmitter
output_high(grn_led_toggle);
output_low(PIN_B5);
output_low(PIN_B4);

delay_ms(1000);
output_low(grn_led_toggle);
output_high(red_led_toggle);
delay_ms(1000);
output_low(red_led_toggle);

}
long read_adc_12(void)
{
long value;

ADFM_BIT=1; //right justify the A/D result
GO_BIT=1; //start the a/d conversion

while(GO_BIT); //wait until conversion is done
restart_wdt();
*Byteptr(value,0)=ADRESL; //get lsb of result
*Byteptr(value,1)=ADRESH; //get msb of result

return(value);
}

main()
{
long int value=0,x=5000;
byte ch;
int i,msb,cksum;
long int value2,batt_cntr=0;
short toggle_var=0;
long led_ticker=0;
short low_batt_flag = 0;

init_hardware();

setup_counters(RTCC_INTERNAL,WDT_36MS); // 36 ms WDT

while(1)
{
restart_wdt();
sleep(); // sleep processor for a while.
restart_wdt();
led_ticker = led_ticker + 1;
if((led_ticker > 50)&&(led_ticker <150>= 500) {
batt_cntr = 0;
//set_adc_channel(batt_input);
ADCON0 = 0x11; // 00010001
delay_ms(1);
value = read_adc_12();
if(value <1400>>8); //sends out MSB of value
cksum=ch;
fprintf(USB,"%c",ch);
//delay_ms(1);
restart_wdt();

while(!input(tx_cts)) {
delay_us(1); // loop here until ok to send data and TX is awake and ready
restart_wdt();
}

ch=(int)(value); //sends out LSB of value
cksum=cksum+ch;
fprintf(USB,"%c",ch);
//delay_ms(1);
restart_wdt();

while(!input(tx_cts)) {
delay_us(1); // loop here until ok to send data and TX is awake and ready
restart_wdt();
}

fprintf(USB,"%c",cksum); //sends out checksum value
//delay_ms(1);
restart_wdt();

while(!input(tx_cts)) {
delay_us(1); // loop here until ok to send data and TX is awake and ready
restart_wdt();
}

fprintf(USB,"#"); //sends out ending framing character
//delay_ms(1);
restart_wdt();
batt_cntr = batt_cntr + 1;

while(!input(tx_cts)) {
delay_us(1); // loop here until ok to send data and TX is awake and ready
restart_wdt();
}

toggle_var = !toggle_var;
if(toggle_var == 1) {
// output_high(led_toggle);
}
else {
// output_low(led_toggle);
}
output_low(tx_enable); // turn off transmitter
}



}

[PCM programmer]

I don't have vs. 2.707. The closest I have is vs. 2.705. I made the
test program shown below and looked at the .LST file. The A/D
functions appear to produce the correct ASM code. This test program
is only for 8-bit A/D output, but it does show how to switch channels.
Try doing a simple program like this one, to see if you can get it
working with two A/D channels.