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Support for Pi Zero 2

See original GitHub issue

Trying out but not working:

Error:

Sending bootcode.bin
Failed control transfer (-7,24)
Failed to write correct length, returned -7
Waiting for BCM2835/6/7/2711...

Or is the new Zero 2 incompatible?

Issue Analytics

State:
Created 2 years ago
Reactions:2
Comments:15 (7 by maintainers)

Top GitHub Comments

3reactions

pelwellcommented, Nov 19, 2021

This issue stems from a bug in the BCM2837A0 ROM, which can’t be modified. The effect of the bug is to stall the USB boot sequence for random (but usually long) periods while changing GPIOs and generally being a nuisance, but sometimes it does actually work - it all depends on precisely what random noise is present in boot RAM when the power is applied.

Fortunately there is an OTP bit that can be set to avoid the problem, but that can’t be set via rpiboot unless you can download code. The plan is to push an update to the regular firmware that patches the OTP of Zero 2 Ws - running this once would be sufficient to fix the device forever.

1reaction

pelwellcommented, Dec 1, 2021

There’s a fresh firmware with the MSD fix in the rpi-firmware repo, as used by rpi-update.