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Why is this condition always true?

Language: C PIC: 16F84A Programm:CCS PCW

When I compile the following code, my compiler complains that the FOR is always true(Maybe the int i doesnt support negative values?):

#include <16F84A.h>
#FUSES XT
#use delay(clock=4M)
byte const display[10] = {63,6,91,79,102,109,124,7,127,103};

void main()
{
   set_tris_b(0);
   while(True)
   {
   int i;
      for(i=9;i>=0;--i)
      {
         output_b(display[i]);
         delay_ms(300);
      }
   }
}

Its PIC Countdown project, so: 9,8,7,6,5,4,3,2,1,0,9,8,7,6,5,4,3,2,1,0,9,8,7,6,... but its stops after the first cycle.

Solution

  • use

        signed int i;

    instead of 

        int i;

    integers are unsigned by default in CCS compilers.

    http://www.ccsinfo.com/downloads/ccs_c_manual.pdf

    Check page 38

    "All types, except float, by default are unsigned; however, [they] may be preceded by unsigned or signed.