Problem uploading to ADAFRUIT Feather 32u4 using Arduino 2.1

You mention you press Reset and then the red LED pulses; do you then also see the device appear in your Windows Device Manager? Does it come up in the Device Manager correctly, or does it come up in the Device Manager as an unknown device?

I think that's a key step in your troubleshooting, because then you can make a decision if it could be a fault with the USB cables or the software drivers installation or a fault with the board itself. It is also a good idea to have another board (could be a cheaper one provided it is using the same ATmega chip) just for troubleshooting purposes.

Some of my 32U4 modules require the reset button to be pushed twice and the timing of the pushes needs to be right for it to work.

Comes up with the correct name in device manager and appears to install drivers properly etc.

Have tried 4 boards which we have on site, all with same issue. can order more boards to try a fresh one?

Thanks for the advice.

Thanks sir, can you elaborate as to how you do it?

Could be a PC issue. If it hangs for 4-5 minutes then the bootloader may time out during that time, which would explain why the output is "programmer is not responding" afterwards.

I don't know if the bootloader times out after 10 seconds or so. You may need to complete the entire exercise within the 10 seconds after reset.

It may be hanging for 4-5 minutes due to a permissions issue perhaps. I don't use Windows 10 any more so I can't comment much here. You really ought to have more than one board so you can narrow down problems quicker. 

Also, make sure that no other hardware is connected, i.e. no additional wiring to your board when you're programming it, just in case there is something unusual going on there.

The first reset just resets the MCU, the second reset puts the MCU into booloader mode via the USB port. It only stays in bootloader mode for a few seconds, so the double reset sequence needs to be performed just before the IDE starts looking for a target to upload to. But there must be time for the USB to be enumerated by the PC before the IDE starts its upload. So 2 reset pushes about 0.4 seconds apart, leaving just enough time for the USB to be enumerated before the IDE starts its program dump. Generally the resets need to be performed well after the compile has started. You may need to experiment to get a feel for the timing.

Did you follow the instructions in the stackoverflow link precisely?

It says to press and hold reset and then start the upload - wait until compiling is complete and you see the “Uploading” message in the status window before releasing the reset button.

Seems clunky, but I’ve had to do that before.

That sounds like the best way to do it (or a reset timed closer to the point where the transfer is about to occur, as Doug mentions). Because the Arduino IDE does its compilation and then transfers, and that may be taking the time that Alexander is referring to, and it is likely timing out of the bootloader by that time!

It's all a mess because in the effort to simplify, Arduino made it actually more complicated. If the boards simply had a separate boot button, none of these problems would occur. Example is Pi Pico with its separate boot button (although then they went and got rid of the reset button but that's another story).

Thanks guys, seems thats where I might be going wrong, will give it another go.

Thank you, will give it a crack later...