Hi Everyone.

I've encountered an interesting problem porting a small application
from a 16C77 to an 18C452. I'm using HI-TECH PIC C on the '77 and
HI-TECH PIC18 C on the '452.

The problem involves reading the 16-bit register Timer1. On the '77,
TMR1H and TMR1L are both readable, and so I declare:

        static volatile unsigned INT TMR1 @ 0x0E;

and do something like

        counter = -TMR1;

and that works fine. The trouble is that on the '452, TMR1H is only
updated (it's really just a holding register) when TMR1L is read, and
unluckily for me

        counter = -TMR1;

compiles/assembles to code that reads the high byte first, then the
low byte, and so the result in <counter> is worthless.

What is an elegant way to stay as much as possible in 16-bit land yet
"persuade" the compiler to read the low byte first?

Thanks,

--

  ______________________________________
   Andrew E. Kalman, Ph.D.   aek@pumpkininc.com

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