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bddbbd.b
04-20-2007, 09:52 AM
I have the unfortunate sensation that a few of the I/O pins on my BS2 are dead. Is there a surefire way to check? I checked voltage across the pins in question after setting them high and got no voltage. Is that the end of the road for those guys?

[Moderator Added Subject]

Post Edited By Moderator (Chris Savage (Parallax)) : 4/20/2007 4:54:26 AM GMT

Mike Green
04-20-2007, 10:21 AM
How are you testing them? I would use a Red LED with a 470 ohm series resistor and connect it first with the cathode to ground and the anode (through the resistor) to the I/O pin and check with a HIGH. It should light. Then I'd check it with anode to +5V and the cathode (through the resistor) to the I/O pin and check with a LOW. It should light.

bddbbd.b
04-20-2007, 09:26 PM
I was checking with a voltmeter referencing the pin and ground. I just tried the LED test, no go on the questionable pins. Is this the end of the line for those pins (or the whole stamp?).

allanlane5
04-20-2007, 10:17 PM
Well, the pin drivers appear to be blown. Parallax will replace the BS2 for you with a nominal charge. I think -- I don't work for Parallax personally, and I've never had to do this myself, but they've made offers to other people in this situation.

For the future, a 220 ohm resistor in series with each pin during prototyping will preserve your pin drivers.