What's Causing Propeller Reboot?

coryco2

I am having a weird issue with a simple pushbutton unintentionally rebooting a USB Protoboard.

The circuit is simple, and I've used it many times before in the exact same way: for each input desired, a 10K ohm resistor is connected to Vss; and a 100 ohm resistor is connected between the first resistor and an input pin on the Prop. At the junction of the two resistors, I connect the normally open pushbutton that connects to Vdd when activated. Usually this works just fine, but for some reason this time one of the pushbuttons is rebooting the Prop.

It isn't a code issue, as I have several protoboards wired and coded the same way and the other ones all work fine. Even the other pushbuttons on this particular board work fine. It just seems to be some issue with this one input (P15, if that matters).

Any ideas what might be going on here?

Phil Pilgrim (PhiPi)

I would check the 10K resistor. If it's shorted, pushing the button will short Vdd to Vss, causing a brownout.

-Phil

coryco2

Thanks, but no such luck-- the resistor's good.

Phil Pilgrim (PhiPi)

Are you sure the push button is connected to the resistor and not to ground -- or not shorted to ground somehow?

Try measuring Vdd with the button pressed.

Phil

coryco2

Hmm. Well, that was apparently the problem, though you wouldn't think so from looking at the connections. I desoldered/resoldered the resistor though, and now it works fine. Thanks for the advice!