Trouble with VREF_HIGH

[Jack// ani]

Hi all,

When I try to compile this program, I get this error “Undefined Identifier VREF_HIGH”. Can’t understand the problem, even EX_COMP.C which is example program from CCS PIC C gives a similar error! Please tell me what this line means setup_comparator(A0_A3_A1_A2);.


#include <16F628.h>
#fuses XT,WDT,NOPROTECT
#use delay(clock=4000000)
#use rs232(baud=9200, xmit=PIN_A3, rcv=PIN_A4)

short safe_conditions=TRUE;

#INT_COMP
void isr() {

safe_conditions=FALSE;
printf("WARNING!! Voltage level is above 3.6 V. \r\n");
}


main() {

printf("\r\nRunning voltage test...\r\n\n");

setup_comparator(A0_A3_A1_A2);
setup_vref(VREF_HIGH|15);
enable_interrupts(INT_COMP);
enable_interrupts(GLOBAL);


while(TRUE)
{
if(safe_conditions)
printf("Voltage level is below 3.6 V. \r\n");
safe_conditions=TRUE;
delay_ms(500);
}
}

Thanks

[PCM programmer]

What is your version of the compiler ?

To find the version, compile a file (with errors), and look at the
top of the .LST file. The version will be a number like 3.191, 3.223, etc.

[Jack// ani]

CCS PCM C Compiler, Version 3.200

[PCM programmer]

Your 16F628.H file is missing the VREF constant declarations.
Somehow, they were left out of your version.
Add the following code below the #use statements in your program.