Russ Hensel wrote:
> My 16f819 project to drive 2 steppers is making me crazy!!! System boots 
> and runs fine sometimes. ( see below for Environment ) but only sometimes.

Wild guess: When it's waiting for a button press at power-on, some 
timers are running.  Once you start the first step, maybe timers and 
interrupts get synchronized for eternity, and if you're lucky it's in a 
good way that masks race conditions, and if you're not, you... lose the 
race.

Can you look at a call tree and determine whether there could be a stack 
overflow during interrupt handling?  Or are there other possible race 
conditions between main code and interrupts?

Can you hack it to remove the button presses at power on, so that timing 
is standardized, and if so, does that change anything?
-- 
Timothy J. Weber
http://timothyweber.org
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