Settings appear to change when USB Disconnected

Questions about using encoders with the Roboclaw product line
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Basicmicro Support
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Re: Settings appear to change when USB Disconnected

Post by Basicmicro Support »

Yes. I received it just before the end of the day(yesterday).
bearbait
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Re: Settings appear to change when USB Disconnected

Post by bearbait »

Please advise if you have had an opportunity to examine this unit yet.
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Bearbait
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Re: Settings appear to change when USB Disconnected

Post by Basicmicro Support »

I have looked at the board. It appears the diode clamp we have on the USB VBus pin on this board is clamping at a bit higher voltage than normal. This is allowing the voltage to go high enough to cause the clamping diode on the input pin of the main processor to start to conduct. This causes the Vcc line to rise slightly above the nominal 3.3v which is also used as the A/D reference. This causes the A/D readings to be slightly different when USB is plugged in versus when USB is not plugged in. The fix is to replace the external clamping diode to prevent the processors clamping diode from conducting.

Unfortunately I dont have any in stock. We currently have a parts order in that should be here sometime next week which has the diode I need.
bearbait
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Re: Settings appear to change when USB Disconnected

Post by bearbait »

Thanks. I will pass this on.
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Bearbait
bearbait
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Re: Settings appear to change when USB Disconnected

Post by bearbait »

Any news?
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Bearbait
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Re: Settings appear to change when USB Disconnected

Post by Basicmicro Support »

Yes. New part fixed the problem. Got them in Thursday and fixed the board. Was going to ship Friday but got sick Thursday night so I couldn't get to it till today. I will email the tracking to the email you included in your note.
bearbait
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Re: Settings appear to change when USB Disconnected

Post by bearbait »

Thanks, all working now. Apologies for delay in letting you know.
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Re: Settings appear to change when USB Disconnected

Post by Basicmicro Support »

Not a problem. No news is usually good news in my book. :)

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