r/AskElectronics 1d ago

USB output problem with MIDI keyboard

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I have an Alesis Q49 MIDI keyboard, in which the USB port doesn't work, but the normal 5 pin MIDI does. It had an issue which is very typical to this product, that the USB type B connector broke off. I soldered in a new one, checked all the connections, but it still doesn't work. The computer says Device couldn't be recognised. I have traced back the data+- lines (shown on picture), it leads through two resistors to two output pins on the microcontroller. When plugged in, both lines have 3.14 V on them, unfortunately I can't check the signal since I don't have an oscilloscope. Is there any way I could fix this?

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u/JPeza 1d ago

Is there continuity from the USB cable once connected all the way up to the micro controller pin?