Dave Turner wrote :

> After much reading up, I found some registers related to timer1.

"Much reading up" ??
Everything about TMR1 is in (just) *7* pages in the data sheet.
And have you realy been "using" TMR1 without knowing
about the registers "related to timer1" ? Seems a bit hard... :-)

> Using my earlier (and finally successful) RS232 program, I tried to
> send the contents of TMR1 every time a button is pressed.  When I
> tried to send TMR1H (most significant byte),..

Have you read the section called "7.5.1 READING AND WRITING
TIMER1 IN ASYNCHRONOUS COUNTER MODE" ??
(Note, it *was* in uppercase in the data sheet, I'm just quoting,
not shouting... :-) )

> it was always d'8', and
> the least significant byte was always changed around, starting at 85,
> then after a few resets, 86, then 87, and finally 83.
> 
> I setup T1CON with:
> 00001011
> and later tried
> 00001111
> 
> That's: system clock not running off tmr1, no prescaler (1:1), osc
> enabled, I tried syncing on and off - no change, tmr1 source is
> external, and tmr1 is on.

The section called  "7.11 Using Timer1 as a Real-Time Clock"
seems to describe a fairly simple method to get a 1 sec real-time
time base. Have you checked if that relates to your needs ?

Jan-Erik.



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