Hello,

I have a Hi-Tech C program that is using enough RAM to require me to place
some extern variables in Bank1.  I'm using a 16F873.

I've read the Hi-Tech C manual, but am still lost at how to properly use the
BANKx.  Specifically, I have a bunch of global variables that I would like
to move to bank1.  All the variables I am moving are global unsigned char's.
From the manual it seems all I would have to do is place BANK1 in front of
them.  If I only move a few variables to bank1 than the program compiles
fine with the memory map:

  Program ROM   $0000 - $03D1  $03D2 (   978) words
  Program ROM   $03D4 - $07FF  $042C (  1068) words
  Program ROM   $0801 - $0EDF  $06DF (  1759) words
                             $0EDD (  3805) words total Program ROM

  Bank 0 RAM    $0020 - $006C  $004D (    77) bytes
  Bank 0 RAM    $006E - $007C  $000F (    15) bytes
  Bank 0 RAM    $007F - $007F  $0001 (     1) bytes
                             $005D (    93) bytes total Bank 0 RAM

  Bank 1 RAM    $00A0 - $00A3  $0004 (     4) bytes
  Bank 1 RAM    $00FF - $00FF  $0001 (     1) bytes
                             $0005 (     5) bytes total Bank 1 RAM      <-
YEAH! Something in Bank1

  Program statistics:
  Total ROM used     3805 words (92.9%)
  Total RAM used       98 bytes (51.0%)

However, if I try to move more variables to bank1 (5 or less depending on
exactly what variables I choice) the compiler fails when linking:

  The instruction at 00404ace referenced memory at 00000000
  The memory could not be read fromEnter PICC -HELP for help
  Serial number: HCPIC-14658
  Licensed to  : DONOVAN PARKS

I thought it might have something to do with the variable being used in the
ISR or not, but this doesn't appear to be true.  Are there some subtle
issues regarding the use of BANKx?  Does anyone have the time to look over
my program to see if I am doing something "silly"?

Thanks,
Donovan

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