Weird problem with my ProMicro

Hi Guys,
I've played around with the ProMicro somewhat and being enthusiastic about de capabilities of this tiny device, I ordered some more. The recent models have even smaller dimensions along with a Micro USB connection, where the others had a Mini USB socket.

Now... I connected a few components in the same manner as I did on the older ProMicro which worked fine.
I had connected the pro micro directly by USB but my laptop gave an error message that the "latest connected USB hardware was not working propper."
And no... I could not upload my sketch.
My laptop did not even see find the right USB port.
Knowing it might have something to do with a bad connection, I desoldered every component whilst testing every step. No success or whatsoever.
Finally, I took another ProMicro and that one did connect correctly... For a brief moment.
My system noticed a Lillybit(?) device connected, but then also... The USB connection was lost again.
I've tried several USB cables on both devices. No effect. The power is on, which can be affirmed by the green onboard LED.
Did I blow something up? I mean... If it has a USB connection, I assume I can hook it onto a USB cable from my system, Right??
Then what is it that causes the devices to die on me...?
Oh, worth mentioning... The second device died even before I managed to upload any code.

Anyone on this?? :confused:

So were they connected to any electronics when you attempted to use them or not? If not, I guess you got bad quality boards. You should post a link where you got them so at least we can read the description instead of being told you had ProMicro.

It appears the boot loader may not have been properly programmed into it. This happens a lot on some real inexpensive boards. I would verify that and if corect ask for your money back.

Tx for the reply guys.
I bought them of Aliexpress and to be honnest, I had them lying around a while before using them.
I've ordered an other batch and I keep in mind to write down the brand in case of the same problems.

The boards waren't connected to anything (at least the second board, same batch.) I desoldered every connected component to rule them out. And to rule out a possible error caused by the removed components, I connected the whole new board.

Both boards seem to work for a brief moment. The boards were recognized, as was the USB port.
Is that possible with boards which were delivered without that bootloader??

I am not sure if this is helpful or not. I bought some “eastern” Pro Micro, and the batch of regulators used appeared to be bad.
I have had a couple of the Pro Micros just pack in without any external load. In the end I used an external regulator and the boards came to life.
I guess just a bad batch.

BUT - I also noted that the 5V and 3.3 variants had different connectors. And one was incorrectly supplied as being the wrong voltage too!
There are 2 versions of the board 3.3V and 5V. Although they should both program OK via USB, you need to check in the IDE that you have the correct processor selected. 3.3V 8mhz or 5V 16mhz. Otherwise the IDE cannot connect.
Check the writing on the crystal.

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Hello bezelsanddisplays,
I am familiar with the difference in power supply and on which frequency the processor runs.
I got my source directly from the USB port. This would be the same as the power supplied to the RAW pin of the board.
I actually chose the 3,3v type due to other components which run on that voltage.

I just received a new batch of 5 and I haven’t given any feedback on the manufacturer… The suppliers are very sensitive to negative feedback, so I have to make sure the boards are working.

Fingers crossed… :wink: