Putting Macbook into DFU mode

During the most recent upgrade, my MacBook seemed to freeze on the update so I restarted. Big mistake.

After it came back up, I got the scary exclamation mark and text that linked to an Apple support page. The page gave me two options: ‘revive’ my Mac, or restore it.

Reviving it meant connecting a USB-C cord between the dead laptop and a working one and then hitting a magic combination of keys on the dead one with the right timing to get it to boot into DFU mode so the firmware could be restored.

I tried and tired but could not get it working correctly.

Googling, I came across a YouTube video that mentioned https://github.com/AsahiLinux/macvdmtool.

I downloaded the software and ran make.

Then, with sudo, I ran the serial subcommand and then the dfu subcommand and instantly the other laptop went into DFU mode. At that point, the ‘reviving’ continued as it should and I shortly had a working a laptop again. Thank you, open source author!