Can't revive bricked Cactus Micro Rev2: bootloader lasts too short

My Cactus Micro Rev2 was working great until I uploaded a bad sketch, which bricked it. I’ve tried following the Troubleshooting wiki page and double pressing the reset button. That does bring up the bootloader very briefly (maybe 5 seconds), but it’s for such a short time, I can’t seem to get any sketch fully uploaded before the bootloader turns off. I’ve tried using both normal Arduino and PlatformIO. Any suggestions?

First, you’ll need to set the serial port to the bootloader. But that port is only visible when the board is in bootloader mode, so pull the reset line low twice quickly to invoke the bootloader reset feature discussed above. You can quickly press the reset button twice. While the Cactus Micro is in the bootloader change the ‘Tools > Serial Port’ menu to the bootloader COM port. Quick! You’ve only got eight seconds. On Windows, the bootloader’s COM port number is usually one number higher than the Cactus Micro’s regular port number.

I did that, and I was able to set COM port. But when I try to upload a new sketch, it fails. I think this fails because the “8 seconds” times out before the upload can finish. I’ve tried many times. What should I do?

You can press the “upload” button first in Arduino IDE. When the status will change to “Uploading”, switch to bootloader mode quickly.

Aha! That worked! Thanks!

By the way, I love your product.

good to know it worked. Thank you.