For anyone interested - Raspberry Pi + Arduino controller

[johntan]

I know I posted awhile ago on here a purely arduino controller, I have started working on a new project though to get the arduino online with a $25 raspberry pi.

The current code is listed here:
https://github.com/johntan/rpicontroller

It is fairly basic for anyone just getting into coding, but has been running my office fishtank for 2 weeks without incident.

Currently it controls temp with a heater and a fan, metal halides, 3 led channels, ATO functions, simulates tides 4 times a day, logs the temp to a .txt file, and operates two dosing pumps based on the time of day down to the minute.

This can operate two arduino's separately so it could run two separate systems if you felt so inclined.

Right now I am working on the website portion which gives current temp, I'd like some nice graphs and to incorporate PH into this as well.

If anyone has a PH circuit done I'd love to know!

 

[jason401]

Awesome! can you get a video of the tide simulator

 

[Fishport]

Looks like a great project, but beyond my needs. I'll be curious to learn more.

Where do you go to buy electronic components?

 

[johntan]

Amazon Hong Kong vendors. Saves a bundle

 

[thomb]

Curious, did you choose the Raspberry Pi/python code as the "brain", serial connection for communication w/ the Arduino "body" architecture for a particular reason other than potentially controlling multiple systems? E.g. a limitation or concern?

I've been working on a controller of sorts, but the Arduino is both brain and body.

I am using of this set of libraries for timing and handling button/sensor events.
http://forum.arduino.cc/index.php?topic=51439.0

They've worked flawlessly/simplified coding, but I have not fired this code in anger so to speak.

 

[johntan]

Sorry just saw this, yes I have found the pi is a dirt cheap way to get the arduino online, and it is MUCH better at time based events. The arduino while very good at reacting to input can get very strange with keeping time.

But yes until about 2 months ago I had the arduino as the brains and body, and that totally worked. It's just much better now, because if I need to check in or adjust the program I no longer have to plug in the arduino, I can just visit the site or ssh to the pi - http://pickles.no-ip.biz

 

[thomb]

Interesting you say that about trouble keeping time. I built a timer for my dad's drycleaning machine and was using this library for timer events:
http://forum.arduino.cc/index.php?topic=51439.0

I started getting all sorts of mixed up timer event results after having about 10 + timers ticking. Didn't have the time to troubleshoot it so I fixed it with brute force - a single, tick every second timer and keeping my own time with variables / evaluating them with a select case. Works but not nearly as clean as having the different events.

The online option is pretty slick! nicely done. I may just have to look into the pi!