Resurrect Pro Micro

Hi Guys,

I have a malfunctioning Pro Micro that you can read about here: http://forum.arduino.cc/index.php?topic=289936.0

ChilliTronix has suggested the Atmega bootloader programmer (Gammon Forum : Electronics : Microprocessors : Atmega bootloader programmer) might be able to resurrect it but to ask here for the experts opinion.

So any thoughts? Can I just use the Leonardo bootloader on it or do I need to do something else mroe complex?

Thanks for your help!

You can use the micro bootloader or the one from sparkfun they both work.

So any thoughts? Can I just use the Leonardo bootloader on it or do I need to do something else mroe complex?

Thanks for your help!

Use the Sparkfun code: here

Thanks guys I will give it a go.

Looking at Atmega bootloader programmer (Gammon Forum : Electronics : Microprocessors : Atmega bootloader programmer) it shows that for a Leonardo you have to connect the two ICSP headers together. The ProMicro clone I have doesn't have these (http://tinyurl.com/ojn2mxs). Any idea if it is possible to re-burn the bootloader of this one?

Do you have access to the SPI pins ?

I have found a schematic which suggests PIN 15 = SCLK, 14 = MISO and 16 = MOSI

If I just hook up to those will it work?

look at the standard example, I think you need to reset the board as well under software control

Sorry to be dense but by standard example do you mean the "Arduino as ISP" example sketch. And by resetting under software control do you mean do a physical reset whilst programming it or do you mean reset it via software?

Sorry I didn't make it clear

Yes. Look at the wiring of an arduino as an ISP

Pin 10 on the Arduino needs to be connected to reset on the pro micro

OK it as been ages I know...damn families :slight_smile:

I have now used Nick Gammon ATMEGA chip programmer sketch on a UNO. When I first connecte dit all up I did a verify and it reported errors. I then reprogrammed it using his Atmega32U4 bootloader which seemed to work OK. I did another verify and NO ERRORS FOUND.

But now when I plug the little Pro Micro into my laptop nothing happens. No unknown device or anything. Just nothing. The pro micro looks OK with the red led sitting there steady.

So any more ideas. Is it dead?

P.S. I found this thread Pro Micro bootloader and driver problem - SparkFun Electronics
It said to use the bootloader from documents>>add on files from here: https://www.sparkfun.com/products/12640

I have had a look and (whilst I dont really know I am doing!) it appears there are some differences in the hex codes. So have I used the wrong bootloader for the pro micro? (ie. Does the leonardo bootloader not work with the pro micro?)

To finalise this something has died with this little fella but I am still able to flash it by using the Arduino as ISP sketch. So kind of all good.