Yes, this is the C that I believe generated the good code.  I can't test now
myself either :-(

Boating season is here!

Andy











"David E. Olson" <dolson@PROGRESS.COM> on 03/21/2000 06:11:49 PM

Please respond to pic microcontroller discussion list <PICLIST@MITVMA.MIT.EDU>








 To:      PICLIST@MITVMA.MIT.EDU

 cc:      (bcc: Andrew Kunz/TDI_NOTES)



 Subject: Re: 16-bit arithmetic in C








First of all, many thanks on the input.

[Various bits from Michael and Andy snipped...]

> union intchar           /* define the union variable type */

I thought about a union too. It, for some late night reason, seemed clunky.
But now that I see it after some rest, it doesn't look too bad. I may try a
few options and see what I get out when it compiles.

> I try and use these constructs to stay away from inline asm wherever
possible, but sometimes it really is
> needed.  You can use this method to access bits in a char or int as well.
Have a look on HiTechs FAQ page at
> http://www.htsoft.com/ for more details.

Forgot to go to the FAQ - perused the PIC archives and Hi-Tech's on-line
discussions.

> At one time I believe I checked and found the HTC generated comparable
code to
> what I proposed in assembly.
>
> I think it does this correctly:
>
>      int counter;
>      counter = (CCPR1H << 8) | (CCPR1L);
>

This is what I thought could be done. While the union gives me access to all
the entities, I'll have to further look to see I need the hi and low order
bytes when I'm done. Chances are, no.

Question for Andy - is the above example what you found to be comparable to
the assembly routine you posted? Unfortunately I'm not at my dev machine
right now to try it out.

-DO