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PeterO
Posts: 5436
Joined: Sun Jul 22, 2012 4:14 pm

Fan overlay working with Pimoroni fan shim

Fri Aug 23, 2019 9:58 am

I now have a Pimoroni fan shim fitted which uses pin 18 , so I added

Code: Select all

 dtoverlay=gpio-fan,gpiopin=18,temp=65000
and it just works :-)
Now I'm sitting here wasting time watching it start and stop 8-) :lol:
PeterO
Discoverer of the PI2 XENON DEATH FLASH!
Interests: C,Python,PIC,Electronics,Ham Radio (G0DZB),1960s British Computers.
"The primary requirement (as we've always seen in your examples) is that the code is readable. " Dougie Lawson

Andyroo

Re: Fan overlay working with Pimoroni fan shim

Fri Aug 23, 2019 11:18 am

PeterO wrote:
Fri Aug 23, 2019 9:58 am
...
Now I'm sitting here wasting time watching it start and stop 8-) :lol:
PeterO
I was going to ask if you where having a bad day but then I thought this would be more entertaining than the tripe on TV most days. Neat solution and bookmarked - thanks for the solution.

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DougieLawson
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Re: Fan overlay working with Pimoroni fan shim

Fri Aug 23, 2019 11:19 am

Does Pimoroni document that on their website? If not you may want to tweet this to them.
Note: Having anything humorous in your signature is completely banned on this forum. Wear a tin-foil hat and you'll get a ban.

Any DMs sent on Twitter will be answered next month.

This is a doctor free zone.

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PeterO
Posts: 5436
Joined: Sun Jul 22, 2012 4:14 pm

Re: Fan overlay working with Pimoroni fan shim

Fri Aug 23, 2019 11:38 am

DougieLawson wrote:
Fri Aug 23, 2019 11:19 am
Does Pimoroni document that on their website? If not you may want to tweet this to them.
Already done so Dougie...
PeterO
Discoverer of the PI2 XENON DEATH FLASH!
Interests: C,Python,PIC,Electronics,Ham Radio (G0DZB),1960s British Computers.
"The primary requirement (as we've always seen in your examples) is that the code is readable. " Dougie Lawson

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clicky
Posts: 424
Joined: Thu Oct 25, 2012 7:34 am

Re: Fan overlay working with Pimoroni fan shim

Fri Aug 23, 2019 4:22 pm

PeterO wrote:
Fri Aug 23, 2019 9:58 am
I now have a Pimoroni fan shim fitted which uses pin 18 , so I added

Code: Select all

 dtoverlay=gpio-fan,gpiopin=18,temp=65000
and it just works :-)
Now I'm sitting here wasting time watching it start and stop 8-) :lol:
PeterO
I've got a complaint to file: why didn't you post it sooner! LOL
Thanks - I'll do it asap, too! :D

itsmedoofer
Posts: 362
Joined: Wed Sep 25, 2013 8:43 am

Re: Fan overlay working with Pimoroni fan shim

Thu Aug 29, 2019 11:39 am

First class, I'll give that a go tonight !! The python tools currently used look nice with the bright lights but there are a lot of dependencies and I'm sitting here with top running looking at it using 2%CPU :)

alphanumeric
Posts: 2296
Joined: Tue Jan 19, 2016 2:17 pm
Location: Sydney, Nova Scotia, Canada

Re: Fan overlay working with Pimoroni fan shim

Sun Feb 09, 2020 1:01 pm

Missed this thread some how. Anyway, I've been running mine this way for a while. I've posted it once or twice on the Pimoroni forums.
I have also added a 10K pull down resistor between GPIO 18 and ground. On shutdown now my fan turns off, no having to unplug my power supply to make it stop. I have also added the following to my config.txt

Code: Select all

 dtoverlay=gpio-shutdown,gpio_pin=17,active_low=1,gpio_pull=up 
This lets me shut down and boot up my Pi by pressing the button on the fam shim.

Code: Select all

 dtoverlay=gpio-shutdown
will also work as the Fan shim button grounds GPIO 3 and GPIO 17 when pressed. If you enable i2c though it stops working and you have to use GPIO 17 instead.

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PeterO
Posts: 5436
Joined: Sun Jul 22, 2012 4:14 pm

Re: Fan overlay working with Pimoroni fan shim

Sun Feb 09, 2020 1:12 pm

alphanumeric wrote:
Sun Feb 09, 2020 1:01 pm
Missed this thread some how. Anyway, I've been running mine this way for a while. I've posted it once or twice on the Pimoroni forums.
I have also added a 10K pull down resistor between GPIO 18 and ground. On shutdown now my fan turns off, no having to unplug my power supply to make it stop.
If you are not using any Hats, you can restore the original power down behaviour with the bootloader configuration.
See https://www.raspberrypi.org/documentati ... _config.md
I don't have any shutdown/boot buttons so it may not work with your setup.
PeterO
Discoverer of the PI2 XENON DEATH FLASH!
Interests: C,Python,PIC,Electronics,Ham Radio (G0DZB),1960s British Computers.
"The primary requirement (as we've always seen in your examples) is that the code is readable. " Dougie Lawson

alphanumeric
Posts: 2296
Joined: Tue Jan 19, 2016 2:17 pm
Location: Sydney, Nova Scotia, Canada

Re: Fan overlay working with Pimoroni fan shim

Sun Feb 09, 2020 1:28 pm

I do believe if you do that, the Pi will no longer boot up by grounding GPIO 3. You have to ground the reset pin or the global_en pin.
With my current setup pressing the Fan Shim Button will boot it up if it was shut down and left powered. And after the config.txt edit it will do a proper shut down when the button is pressed. And with my pull down resistor mod the fan turns off on shut down. It has to be commanded on once you do the mod though. It will not start up all on its own anymore.

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