Where did you get the adapter for that light pipe? I haven’t found one that fits perfectly yet.
That one didn’t fit that we’ll either… I used a hobby knife to trim it down and then hot glued it in place it’s much easier to see the colors they are more mixed together rather than 3 color dots
That’s awesome, thanks for building / sharing! 
Totally gorgeous! Can we buy these somewhere?
Not quite yet… This is the first build ever and still requires testing and I’ve messed the library up somewhere and it’s not working just yet
I have had a motor turning controlled by the spark so that’s something I guess, but I’m missing 8 bits somewhere and data is coming back a tad later than I expected
I’ll keep everyone posted when we start building a few more
Hi there, I have a 12v Peristaltic pump and the Spark Relay Shield, I’m going to run the pump through 1 of the relays and power it and the Spark core using a 15v plug through the relay board power inlet.
My question is I’m going to use a LM2585T regulator http://cpc.farnell.com/texas-instruments/lm2585t-adj/switching-reg-3a-12v-2585-to2205/dp/SC08551?in_merch=Products%20From%20This%20Range to ensure a maximum of 12v to the pump but I don’t understand what/if I need to use the ground pin for?
Any help would be fantastic!
Hi @apios that regulator you are looking at requires lots of extra components… like a 47uH inductor and diodes etc. It works by flicking the power on and off 100000 times per second. It’s actually very similar to the regulator on the spark shield (although higher current and voltage).
That style of regulator is probably not the best way to drive a motor, it’s internal ‘computer’ is too complicated and will struggle to keep a good steady output voltage when driving a big inductive load with high levels of back emf.
There is a few examples above using a FET or transistor arrays that would work well. I have also designed a motor controller board the same size as the core that will run 2 DC motors but the component cost may be a little high for some (about $40 in single quantities from digikey). Another perfect option would be a polou stepper motor driver for a 3D printer (will also do 2 DC motors) they are cheap and have a high input voltage range, but will require more pins on the spark and a complicated program to run
Thanks @Hootie81 that was a quick reply, to be honest in a programmer by trade and a newb to electronics, so I’m not the best at understanding the diagrams, if it’s not too much hassle, what should I buy just to ensure I don’t overload the motor?
I’ve directly connected the pump to a 5V plug to test it and it’s too slow so I’m trying to get the best out of the 12V.
Thanks again!
motor voltage ratings can be a little miss leading… i run 5v motors on 24v without any issues and they generate very little heat… but i have to use PWM. the higher voltage gives much more torque but i can only have it on for 25% of the time to give an average of about 6v for the motor rating (actually i normally run it much higher than 25%).
how long do you intend to run the pump for? if its only 30 seconds once an hour then you shouldn’t have issues with heat anyway running a 12v motor at 15v, if it was running at high load for long periods it would be a different.
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I just wanted to update this project, I had to take a break for a while Since then I decided to change the programming direction and thanks to @Ric and @bko I was able to complete the programming, and now I just need some help to complete the html/javascript.
Here is that thread - Peristaltic Doser - Doser set amount over 24hr period