>
>Could you please explain a little this feature and its workaround?
>Is it about arrays or about having too many global variables?
>
>....for us who are trying to decide what C compiler to buy.
>
>Thanks
>
>Carlos V. Gutierrez Fragosa - Hermosillo, Mexico
>carlosg@sca.com.mx  http://www.sca.com.mx


Here goes, Carlos:

The 16C505, for instance, has 72 RAM locations.  The CCS compiler, without
any workarounds, only recognizes 24 RAM locations because of a limitiation
they use in the number of bits of address space for this RAM.  So if you
declare more than 24 bytes of RAM, you get an "OUT OF RAM" error.

The workaround is like this:

#BYTE    x    0x30                // declares an integer variable X at the
first RAM location in bank #2 of RAM

or

LONG Y;
#BYTE  y = 0x31           // declares a long integer Y at the second and
third ram location in BANK #2 of RAM.

For ram in Bank 0, the compiler keeps track of whether you have used a
variable, whether it is a temporary variable that can be used by another
funciton, or whther it is a global variable, etc.

For Ram in Bank 1+  YOU must keep track of this information, the compiler
will happily walk on your variables if you tell it to.  Just like the old
days with assembler.


Likewise, the RETLW instruciton does not work in the CCS compiler for table
lookups.  THe workaround is to use the more standard C syntax:

BYTE CONST TABLE [16] = { 0,2,1,3,4,5,4,5,3,6,7,3,4,5,4,3}

x = table[5];   // looks up constant data number 5

This code generates the RETLW instruction in the assembled version, and
RETLW works fine if the compiler generates it, just not if YOU type it.


Other than these problems I've been able to work pretty smoothly with CCS.


So far, I am voting for sticking with the CCS compiler.  Last week I was
really hacked off at it, and would have chucked it out the window.  I do
this with my cars, scopes, meters, computers, etc.etc. on a regular basis.
(get mad, I mean, not chuck them out the window.)

So far I'd say the CCS compiler is worth the money, thier tech support is
adequate but not excellent, thier compiler works adequately but not
excellently, and you get what you pay for.  Realizing I paid  the minimum
price for this software, it is meeting my minimum expectations.  If you
can't afford a better package, it will meet your needs.
If I can ever scrape up $600 or $700 I'll try out the other guys.