emonSD-17Oct19 and Rasberry Pi 2B failure - clock speed too high

emonSD
1

I just spent a few hours getting to the bottom of this one. The solution is mentioned in a few places in these forums, though not obviously found from the symptoms. (Which is why I’m creating this new topic)

The clock speed specified in boot/config.txt is too high for the Pi-2B.
The board will boot, and proceed with startup process, but at some point things will get flaky, or it may hang etc. etc.

Solution:
Edit config.txt and change arm_freq=1200 to arm_freq=900 (or 700 if being very conservative).

Probably distributing a version of config.txt that uses conditional sections as mentioned here would avoid the need for editing.

Meanwhile, it might be good to mention on the upgrade page that this edit is required if you’re using an older (V2) Pi.

1 Like
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Yes there is an Issue open. I just comment out the changes completely and let it use the defaults.

@TrystanLea @glyn.hudson - another one - can this get fixed please?

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@borpin do you have a link to an issue tracker for this?

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No need to drop the clock speed to 700 on a Pi 2 as its rated clock is 900 MHz.
However, 700 MHz would be the correct choice for the original Pi. (sometimes referred to as the Pi 1)

6

As I say, I just comment it out completely.