pri-update stops PPS working

You've fallen foul of Device Tree. It's the new way of configuring certain peripherals and has been activated in the 3.18 version of the RPi kernel.

Try reading this for more information and how to fix things or go back to the old method.

TL;DR: add "device_tree=" to your config.txt and reboot. That will revert to the old method - for now... later you should look at using the Device Tree config properly.

On 27/01/2015 16:22, Dom wrote: []

Thanks for that, Dom. I got further information from Chris Stenton, to whom many thanks, and updated my Web page here:

I trust that this is now the "proper" method.

for info, just updated to 3.18.5+ #744 PREEMPT Fri Jan 30 18:19:07 GMT 2015 armv6l with apt-get dist-upgrade, and the machine becomes unusable unless I kill rpi-gpio-ntp (user mode pps) as it uses >99.5% cpu! I could not eve n ssh in until I had unplugged gps and rebooted.

I was also getting clock drift of > 1 second per hour!

do I need to change to kernel mode pps?

best regards Dave

PPS is now compiled into the kernel, so the user-mode PPS is no longer required. The invocation of PPS has changed, though. Please see the updated quick-start page for details: