I’m going to try to use my new RFM12B based JeeNode Micro from JeeLabs to talk to a Raspberry Pi equipped with another RFM12B. Although the radio module (and JeeNode) are from JeeLabs, I’m going to connect it to a raspberry pi using an Eve-alpha board I got via the Ciseco kickstarter a while back. […]
Read More…Command line control of arduino using ino
As we’re going to be programming the arduino via the raspberry pi over ssh, we need a command line tool to talk to the arduino. Luckilly several such ways exist, including make-files from several sources. I chose to use a tool called ino which seems to have packaged up the toolchain in a fairly decent […]
Read More…Setting up a Pi from bare Raspbian to work as a Node-Red controller
Here is a set of instructions to go from bare Raspbian to work as a Node-Red controller and also send text (sms) alerts using a 3G usb dongle. For various reasons I’ve needed to retrace my steps a few times, so here I’ll document them all for my and your convenience. Starting point is a […]
Read More…Using the ACS712 Low Current Sensor
Gareth and I are using ACS712 Low Current Sensors in our Aquaponics project. We’re using them to measure AC current. All we really need them to tell us is whether various pumps are on (and drawing 1/6 of an amp) or off. The raw value you get when you do an analogRead on the pin varies […]
Read More…raspberry pi running node-red, wiring-pi to pwm control a light
OK so putting node-RED on the raspberry pi was almost as easy as getting it onto my computer – see previous post here. I started with the occidentalis distro from adafruit – and to install node.js itself I needed to use different package to match the pi wget http://node-arm.herokuapp.com/node_latest_armhf.deb sudo dpkg -i node_latest_armhf.deb but apart […]
Read More…Tweeting with Node-RED via a mqtt broker
Having had a wonderful weekend at Wuthering Bytes, I decided to try and install the fabulous Node:RED tool and try to use it with mqtt to tweet the light level. Firstly Node-RED depends on node.js, so I installed node.js via Chris Lea’s ppa – he seems like the right sort of person to package up […]
Read More…Fixing Technics 1210’s
A friend of mine rang up the other day and asked if I could help fix a Technics 1210 record deck. For the uninitiated, these are the decks that DJ’s around the world use (or used to use) for mixing old fashioned shellacs (sorry, records). Now you may think that playing music by spinning an […]
Read More…Transistor calculations for a 12V 300mA light via raspberry pi gpio pin
I am following this excellent page as a guide: http://teachmetomake.wordpress.com/how-to-use-a-transistor-as-a-switch/ Using it, I worked through my use case of an raspberry pi connected to a TIP120 to drive a 12V LED light. diagram from http://ctheds.wordpress.com/2007/10/30/tip-120/ What value of resistor should I use? I’ve seen several different values on web examples, so looks like I need to actually […]
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