Single Board Computer Controllers

[twofer]

In another thread about controllers the use of single board computers (SBC) as a controller was brought up and I thought its own thread might be in order as I am interested in setting one up for my system. A setup like this would allow me flexibility in the future as well as help me overcome the current hurdle of handling a 10 degree difference in my heating stages that current multi-stage thermometers cannot handle.

For you guys that already have an SBC setup to control your system would you mind providing details about your setup?

 

[Nofossil]

See my signature ;-)

There are a few who have built controllers based on this design, but not for the faint of heart when it comes to the software. I'm working on a version that will be programmable via a web interface, but it's not ready for prime time yet.

 

[twofer]

Nofossil, actually that was the first place I looked! Your website is a wealth of information. With that being said the reason I posted this thread was because I just wanted to see what everyone was using.

 

[free75degrees]

I’m using a ts7800 single board computer running linux, similar to the one that nofo uses (same manufacturer, Technologoc Systems). I get the temps using Dallas Semi ds18s20 sensors. The sensors interface directly to a dio24 pc104 board that is also made by Technologic and plugs right into the ts7800. I wrote the C code to read from the sensors. A separate Perl script runs once a minute and calls the sensor program to get the temps. It then uses the temp data to decide which state the system should be in and calls another C program that sets some I/Os that control relays that control the valves and circs in the system. The relays are all interfaced from a separate dio24 board from the one used to interface to the sensors. The Perl program also logs the temps and state info and a separate Perl cgi script parses the log and produces a graph of the running system state.

 

[WoodNotOil]

I am using an Arduino USB board which from my understanding does not have as many I/O and lacks a few other features as the system Nofo uses, but it is about $35. I am using the Dallas 1-wire sensors so I don't need as many I/O and you can actually hook multiple boards together in the end to expand the system. I am starting by making a differential storage loader with 2 sensors and a solid state relay. I just got the board to actually read the senors yesterday. Now I can work on my code and run my wiring down to the boiler and storage tank. I am excited about the possibilities this adds to my system.