HotPi

[IriDium]

As regular readers will know, I love playing around with my RPi trying new things and suggesting new things.

I do it because I enjoy it, not that it adds any benefit or advantage to Xbian.

So recently I have been playing around with HotPi - a new GPIO addon for the RPi. HotPi
For 11 squid it gives software LED and FAN control, with the added bonus of a real time clock, and an IR port which is supposed to work with any IR receiver.

First things first - It's a kit - so if you have shaky hands or don't own a soldering iron, this is not for you. But with a bit of patience you can solder everything together.

Following the installation instructions Instructions is straight forward. (There are bits missing like type of battery but all in all not too bad - I have been informed that it in the process of being rewritten so hopefully some of the problems will have been removed)

The RTC (Real time clock) does not work on default Xbian because the required module is not loaded into the kernel.

I haven't tested the IR functionality so can't comment just yet.

The LED and Fan control programs compile without errors on Xbian and work because we use upstart.

Any 5V fan should work directly - I'd recommend a low noise 40mm depending on your requirements and enclosure.

Note: The current design will not fit inside a standard RPi enclosure (This could have been avoided but..)

....... so it's all now working

You can control the colour of the LED lights by just calling the program (all detailed in the instructions) and parsing the colour you want in hex = so red is FF0000. Obviously the colours are not precise but you can play around.

The fan speed is similarly controlled with a value of 0=off to 255=full (Note full is not the fans full speed but about 75% as the voltage at 255 is only 3.3V.

Was it worth it?

Yes, it was good fun and I'm slowly rewriting my earlier script to incorporate it. I think for what it offers and at the price for 4 bits of HW control its a bargain - especially as the last time I looked a RTC only was £10 and the Hotpi is only £11

Issues I had:
1. Nothing worked!!!! Advised to check soldering.
2. Worked - but fan not switching off - check soldering again.
3. Many of the daemons didn't work - this is because of the difference between wheezy and Xbian in how they get the temperature.
4. The hotpi-daemon uses 7% cpu - which is a lot and the developer is aware of this.
5. My new case, an old mobile phone box. Because of the hight problems, the LED was not visible, so I just cut a hole where the LED was and plugged it with a piece of 10mm (I think) glue stick - actually looks better than the pure LED.

So a plus point for kickstart.

The developer is also very helpful if you have any problems, a plus point for a lot of small start ups.

BTW: Don't reply if you want to say that the RPi doesn't need temperature control (I know that)

[CurlyMo]

Nice guide. Didn't knew this thing existed. However, i don't understand your enthousiasm.

First, (i have to say this to make the rest of my points ), when are you going to stop bother about your RPi temperatures. You aren't going to break it on temps. So the fan controller is quite useless.

Second, the price is quite high.You can buy an:
IR receiver TSOP4838 for $0.99
IR sender for $0.93
RTC for $1.40

And if you really want to:
RGB led $0.99 for two.

Third, the programs are really bad if they use that much resources. I believe you really have to offer more for a kickstarter project.

For about $ 5 i can solder myself a nice small board that i can put directly on my RPi GPIO. And what programming does this thing need? It only has to check the temp of the RPi and control a small fan. I'm running pilight with hardly any resources (about 1% CPU every 3 sec.). There are already great and efficient RPi programs available for the RPi and for IR we already have Lirc.

That would make a total of $ 3.50 --> £ 2.15. The nice thing is that you are not going to block any non-used GPIO pins.

[IriDium]

(9th Dec, 2013 04:05 AM)CurlyMo Wrote:  Nice guide. Didn't knew this thing existed. However, i don't understand your enthousiasm.

First, (i have to say this to make the rest of my points ), when are you going to stop bother about your RPi temperatures. You aren't going to break it on temps. So the fan controller is quite useless.

A small but very significant point. RTFM
QUOTE!!!!

BTW: Don't reply if you want to say that the RPi doesn't need temperature control (I know that)

---

@CurlyMo Great where can we buy this £2.55 board? Complete with software, postage and support. Send us the link!

[CurlyMo]

If you can solder this, you can also easily built something like this yourself on either a breadboard of soldered.

If you really want to use a fan controller, that can also be built in about 30m (software wise).

[rikardo1979]

(9th Dec, 2013 05:06 AM)CurlyMo Wrote:  If you can solder this, you can also easily built something like this yourself on either a breadboard of soldered.

If you really want to use a fan controller, that can also be built in about 30m (software wise).

as you saying, all these can be build pretty easy and really cheap buying the bits from local suppliers.
But I think same as you, the fan and temp controller on RPi is pretty pointless/useless, but if somebody wants to do than why not

[CurlyMo]

Regarding the fans:
http://www.ebay.nl/itm/Brushless-DC-Cooling-Fan-5-Blade-5V-12V-0-1A-25mm-x25mmx10mm-2510s-2-PIN-/260919629656?pt=LH_DefaultDomain_0&hash=ite...3cc0059758
http://www.ebay.nl/itm/Brushless-DC-Cooling-Fan-7-Blade-DC-5V-25mm-x25mmx07mm-2507-2-Pin-Wire-0-1A-/290881774636?pt=LH_DefaultDomain_0&hash=...43b9e7a42c
http://www.ebay.nl/itm/Brushless-DC-Cooling-Fan-5-Blade-5V-0-1A-25mm-x25mmx10mm-2510s-2-PIN-NEW-/261216792639?pt=LH_DefaultDomain_0&hash=ite...3cd1bbf03f
http://www.ebay.nl/itm/1pc-DC-Cooling-Fan-5V-0-1A-25mm-x-25-mmx10mm-2pin-2510-/180551752714?pt=US_CPU_Fans_Heatsinks&hash=item2a09b91c0a

All 5v 100mA so should work fine directly on the 5v + GND of the RPi.

[IriDium]

Well after many hours of playing - I ended up by just attaching the 25mm fan (21db) to the 3.3v GPIO pins and let the fan run all the time.

It's not noisy (even when nothing is playing), doesn't consume any CPU and keeps my RPi at around 30 degrees.

I did run it at 5v but it was a bit too noisy when nothing way playing.

Would like to see what the difference would be without the heatsinks but alas they are now stuck on - doh.

So: Get some heatsinks and a fan - and sorted!!!!