 | | Re: pcode downloading —Fred G. Martin
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| | | Here is the relevant part of the test instructions: Finally, the MAX232's ability to transmit data to the host computer is tested. Again using pin 7 of J9 as a ground reference, measure the voltage at pin 3 of J9. This is the MAX232's serial output. (...) (28 years ago, 3-Jan-97, to lugnet.robotics.handyboard)
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| | | | | Re: pcode downloading —Karl Altenburg
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| | | | (...) : (...) I get -8.9v when its not jumped. When jumped I get some floating values in the mV range. I checked all of the solder joints. Changed power supplies. Removed and reseated the chip. Checked power and continuity at various points around (...) (28 years ago, 3-Jan-97, to lugnet.robotics.handyboard)
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| | | | | | Re: pcode downloading —Fred G. Martin
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| | | | (...) OK, well I think it is isolated at the pseudo-MAX232 chip. Did you get the +10 v power supply pin on the p-MAX ok? It's at pin 2. Measure it w/r/t ground and you should get +10v. Before you order a real Maxim, check the polarity of your (...) (28 years ago, 3-Jan-97, to lugnet.robotics.handyboard)
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| | | | | | Re: pcode downloading —Karl Altenburg
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| | | | (...) Yep, that checks out. (...) I get the correct voltages for the caps. And if the wrappers are on correctly they should all have the correct polarity. I ordered a replacement MAX232CPE (not the high speed "A" version). Hopefully this will either (...) (28 years ago, 3-Jan-97, to lugnet.robotics.handyboard)
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