I am working with the 16F684, using the BoostC compiler and the MPLAB IDE.  I am learning how to use the A/D converter.  For now, I am reading in a voltage and turning on one bank of LEDs if it is less than a target value, and the other bank of LEDs if it is greater than the target value.  Pretty simple stuff.  

The first part of the code seems to work and is 
  int adc_result;                   //integer for storing 8 bit a/d result
  void main()
  {
   cmcon0 = 7;                    //turn off analog comparators 
   ansel = 0b00001;             //select AN0 (pin 13, RA0) as A/D input
   adcon0 = 0b00000001;     //turn on A/D, select RA0/AN0 as input, don't start conversion
   adcon1 = 0b00110000;     //select internal RC clock
   intcon = 0;                      //turn off interrupts
   t1con = 0;                       //turn off timer 1
   porta = 0b111111;
   portc = 0b111111;
   trisa = 0b000001;             //set port a as output, except RA0
   trisc = 0b000000;             //set port c as output

   while(1)
   {
   delay_ms(500);                //delay between loops
   set_bit(adcon0,1);            //start a/d conversion
   while (!test_bit(adcon0,1)); //wait for completion
   adc_result = adresh;         //store a/d result
The following code works
.
.
.
  if(adc_result<0x0F)  //if a/d count is below F then
    {
    porta = 0xFF;    //turn on port a
    portc = 0x00;    //turn off port c
    }
    
   if(0x0F<=adc_result) //if a/d count is above or equal to F then
    {
    porta = 0x00;    //turn off port a
    portc = 0xFF;    //turn on port c
    }

but this code does not

  if(0x00<=adc_result<0x0F)  //if a/d is below F then
    {
    porta = 0xFF;    //turn on port a
    portc = 0x00;    //turn off port c
    }
   
   if(0x0F<=adc_result<=0xFF) //if a/d is below F then
    {
    porta = 0x00;    //turn off port a
    portc = 0xFF;    //turn on port c
    }

I'm sure I am overlooking something simple, but after a few hours of experimenting, I am stuck.  I'd appreciate any help.
Thanks.
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