AVR-Chat

--- In AVR-Chat@yahoogroups.com, "arhodes19044" <spamiam@c...> wrote:
>  
> When the 2 timers are running simultaneously then I get the timer 1 
> output compare triggering the timer2 overflow function (I can't 
tell 
> if the code is jumped to, or if there was an interrupt to get 
there).
> 
Tony,

It isn't possible for a timer1 OC to trigger a timer2 interrupt 
service routine.  When an interrupt occurs (and it's interrupt flag 
is enabled) and interrupts are also globally enabled, the AVR vectors 
to an address reserved for that interrupt.  At that address, another 
address will be found which is placed there by your compiler.  This 
is the memory address at which the compiled interrupt service routine 
has been placed.  Guessing that your code is written as standard 
interrupt service routines are, the only "normal" way to get there 
would be through an actual interrupt (not a "jump" or "goto" 
unrelated to an interrupt).

What chip are you working with (this will help with register 
identification) and does it have JTAG?  Perhaps this 
is just a simulation issue (as you suggest) and not a real world 
issue.