Could be my lucky day today… not only does the Orange Pi PC work but I’ve been talking to a pal of mine Peter Oakes (check his videos) in Canada… I know zilch about Linux apart from what seems like several thousand commands I’ve learned recently (probably a dozen) be necessity – however, I was getting a little concerned that the Orange Pi even with a tiny heat sink tends to get a little warm and I thought it might be nice to get that info – and be able to turn a fan on instead of the normal response when they get too hot which appears to be to shut down!!!
Anyway it turns out that this command…
cat /sys/devices/virtual/hwmon/hwmon1/temp1_input
returns the temperature as a decimal. We THINK a similar one for the Raspberry Pi is this.
cat /sys/devices/virtual/thermal/thermal_zone0/temp
Though in the latter case, it returns sometimes a 5 digit number which seems to include the decimals… not sure how to reduce that down to the same as the Orange Pi – maybe integer divide by 1000 ( or am I reading the wrong one) – both of these react appropriately to an air canister.
ANYWAY in order to use that in Node-Red – and hence send an email or turn a fan on…is to use the EXEC node – so in the case of the Orange Pi…
Well isn’t that handy – press the button and out comes the temperature of the chip – it doesn’t take much imagination to replace the left with a timer – maybe once every 30 seconds – and the output with either an email or GPIO control for a fan.
So – Orange Pi and Raspberry Pi experts – where is there an idiots guide to all the other useful addresses to get info ??
http://www.orangepi.org/orangepibbsen/forum.php?mod=viewthread&tid=785&extra=page%3D1
Funnily enough I set this up on my Pi Zero at the weekend when I decided to put inside a small plastic case.
The command is
/opt/vc/bin/vcgencmd measure_temp
This returns something like:
Temp=37.1’C
So now in Node Red I have an Exec node that runs the above command which is triggered by an Inject node every minute. It outputs to a Function node which extracts the 37.1 bit from the string, and then feeds it to a Node Red UI node that puts the CPU temp on my dashboard along with all my other temperatures.
Thanks David – that does work on the Raspberry Pi and looks nicer than the figure I got out (same data)…. doesn’t work on the Orange Pi so for now doomed to using 2 different commands.. however – better tan nothing… I’m going to try the other solution in here to drop the temperature of the orange Pi… it really is too hot – 60c I could handle…. but it is nearly 80c – fine here but in Spain in the summer it might just go over the edge.
I’m not sure about the temperature value.
However, in case you’d rather not use a fan, you could reduce the CPU frequency as mentioned @ http://forum.armbian.com/index.php/topic/504-quick-review-of-orange-pi-pc/. For example:
echo interactive > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governorecho 240000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
echo 600000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq