In SX Microcontrollers, SX/B Compiler and SX-Key Tool, dkemppai wrote:

[quote="JDOhio"]
I had another thought after reviewing the 555 trigger with a scope. It seems that the cycle of SLEEP and power on is triggering the 555 oddly. Could it be that the default state of the ports affects the timer differently at the lower voltage?

Joe[/quote]Joe,
 

Watch out for pin directions on the I/O ports. The direction register and the values of the pins can be lost during wakeup from sleep (reset).  

 

When you put the SX to sleep, the I/O pins hold their state. However when you wake it up, there is a reset timer that runs before the chip starts executing code (something lik 60mS). During this time period, the pin states are lost (the pins are reset to inputs). User code has to reset them to their previous state. When the pins get set to inputs, the output values are lost.

 

FYI. If you rely on your outputs being in the same state after your code starts up again, you will need to 'shadow' them to temporary registers before you put the SX to sleep, then restore them when the SX is reset again, before your code tries to read the Output Pin States...

 

I don't know if this is your trouble, but it's worth looking at!

 

-Dan

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