Compute Module • Flash image a second time on CM5

Hi,

I went through the process as per https://www.raspberrypi.com/documentati ... odule-emmc once, it worked, I've a functional linux installation now on the pi.

I want to flash it again, because it's mounting file system as tmpfs and my (possibly wrong) understanding is that it needs to be flashed with correct settings (if this is wrong, appreciate a correction, though it would still be interesting to know why I can't flash the OS again).

What I did the first time:

- Disable EMMC boot with jumper
- Clone and start rpiboot (on mac, https://github.com/raspberrypi/usbboot)
- Power the pi

rpiboot detected the pi, and everything worked as expected.

But this time rpiboot doesn't want to detect the pi (I've not pulled or called `make` again on usbboot, so it should be same binary as first time).

I also notice that when the jumper is set, the fan gets very loud and doesn't stop, which I don't remember happening the first time.

After this the pi still boots normally and everything still works as left by first installation, when the jumper not set.

Any ideas? I've tried multiple times. Do I maybe need something to "reset" the device so the initial procedure works again?

Thanks

Statistics: Posted by begin — Fri Jun 05, 2026 7:05 pm

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