Rebooting the Pi won't solve all FO1080 lockups though! What kind of things go 'awry' on your RPi - I've not had (touch wood) any weewx RPi issues in a few years, and usually only get one FO usb lockup a year - which usually necessitates completely resetting the FO1080 - removal of batteries etc., so a watchdog would not help in that situation. I do use a powered hub and hard disk though but power the RPi from the hub. I use a power lead to the RPi with a switch on it so rebooting is easy - just cycle the power with the push button.
On Tuesday, 13 September 2016 07:48:16 UTC+3, Ian Boag wrote: > The dreaded watchdog. An all-purpose solution to stuff that misbehaves for > poorly understood reasons. > > I run a FO 1080 with 4 cameras and a cellular modem from a weewx-powered > Pi and sometimes things go awry. > > I made a watchdog timer using a 555 and some bits. Set the timeout at > about 4 minutes so that it doesn't trigger during boot. I can let anyone > who wants have the circuit. I even got a PCB made ... > > Anyway the watchdog gets patted every couple of minutes. As people > probably know, a 555 astable uses an RC network to charge a capacitor. When > the capacitor is charged it flips the output, then (because it's an > astable) flips it back again. I have the timing set to about 4 minutes on > and 30 seconds off. Patting the dog is a GPIO lead to an NPN transistor > that shorts the charging capacitor to ground. A few lines of python that > runs on startup. > > I have my setup wired up with 12V input from a wall wart. That goes into a > couple of buckies - one set to 5V for the Pi, modem and cameras and one > giving 3V for the sensors. So when the power gets flicked, everything is > recycled. That seems to do the job .... The watchdog of course runs off the > input 12V and controls a relay that manages the 12V going into the buckies. > Wonderful things buckies - cost absolutely zip and make voltage shifting a > breeze. I can plug in anything between 9v and 30v ... > > If I execute <shutdown-h now>, the Pi shuts down. A minute or three later > (depending on where the watchdog was in its charging cycle, the power is > recycled - for the Pi, modem, cameras, sensors - the lot. As the Pi is not > doing anything at the time the on/off is pretty harmless. > > I took out the auto-ftp and replaced it with a "manual" one that I run > every 15 minutes after I have done wee_reports to get the latest upload. I > wrote a bit more python that reads the latest index.html to make sure > everything is as it should be. If not, it just skips the upload and shuts > the Pi down to wait for a reset. > > > > > > -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
