Mega 2560 not recognised

Hi, I have a few MEGA 2560s, some have a USB B socket and some have a micro USB socket.
The USB B ones all work fine and are recognised by my Mac and Windows computers.
The micro USB ones don't.

Google searches haven't revealed any solutions, although it did highlight one difference: I think it's the USB-serial chip and on the USB B versions, this is CH340G 205696B11, and the micro USB ones have a CH340G 205696A46 chip.

However, doing a google on those reveals NOTHING. Which is weird in itself, I reckon.

Anyway, I've tried multiple USB cables and don't think that's the issue.

It does seem to be some hardware difference between the USB B socketed arduinos (which have a blue PCB incidentally) and the Micro USB arduinos (which have black PCBs). All bought off AliExpress, but I've tried half a dozen of these Micro USB ones and can't get them to work at all.

TIA, Simon.

I suspect that your MicroUSB cables are charge only; I know that you mentioned that you tried different cables but they might all have been charge-only.

If you have a cellphone with a MicroUSB connection, you can test by connecting your phone to a PC; if the PC recognises the cellphone, that cable should also work with your Arduinos.

What happens in Windows device manager when you connect a board? Nothing would indicate a charge-only cable or a damaged board. Yellow exclamation marks or unknown devices would indicate a missing driver but that's unlikely if other boards with the CH340 work. For CH340, it should look similar to below (you can compare it with your other clones)


Thanks, and against my best judgement, I thought "Okay, I'll try one more micro USB cable, and IT WORKED! I must have a bunch of charge-only cables as this must have been the eighth one I tried. Still, result: Thank you very much indeed.

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Take all of your charge only cables and put a bread tie or a piece of velcro or even tape on them so you never mix them up again.