TrafficHAT from RyanTeck for the Raspberry Pi – review

The TrafficHAT from RyanTeck is a simple-to-use add-on board for later models of the Raspberry Pi. It plugs into the 40-pin GPIO header and gives you access to 3 large LEDs, a button and a buzzer. It sounds simple, and it is, and that’s the beauty of it. The kit comes in a bag:

and contains all the bits you’ll need to solder onto the circuit board. The GPIO header and the resistors are pre-soldered surface-mount components so all that’s left is to solder the LEDs, buzzer and switch. For the experienced solderer, this will take less than 10 minutes. For a beginner, it will obviously take longer than that but it is excellent for teaching you the basics of soldering because of the large components.

Programming it is very easy and can be accomplished using both ScratchGPIO (which Ryan has personally modded) and, of course, Python. I knocked up a quick Python script just to test the board out and the results can be seen in the short video below:

The TrafficHAT is the natural successor to the Pibrella, although it doesn’t have the protected inputs and outputs of the older board. It also doesn’t break out the unused GPIO pins, which means it’s use is limited. But that is its charm – it’s simple. It’s simple enough to put together and simple enough to program and is ideal for anyone who wants to learn how to program real-world electronics from the Raspberry Pi.

Rating: 9/10

The TrafficHAT will soon be available directly from RyanTeck for £7.75 plus postage (£1.50), and as an introduction to programming and soldering I believe it’s well worth the money.

Learn about Big Data with Hadoop on the Raspberry Pi

Carsten Mönning over at the SAP Community Network has written the start of an intriguing series of blog posts on creating a Hadoop cluster with several Raspberry Pi 2s. This initial post just covers setting up Hadoop on a single Pi, and future instalments will go into further depth on getting a proper cluster set-up and interacting with it. This is an extremely useful skill to learn and I hope people follow the series as it progresses. Read the first part here.

Driving NeoPixels from Docker on the Raspberry Pi

The guys over at Hypriot have been using Docker a lot. In this instance, they use Node.JS to drive a set of NeoPixels from the Pi. In the example, they use the Pi’s 5V power supply to provide the power directly (although this is not recommended) and an Adafruit level shifter to convert the PWM signal on pin 18 to 5V to provide the signal required for the NeoPixels. Read more here.

Use an external drive to drive your Raspberry Pi

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Over at Adafruit, Brennen Bearnes has written a great tutorial and helper script that will enable you to use an external drive as a “root partition”. This means that although your Pi still boots from the SD card, thereafter everything else is handled by the external drive. He’s used a full-sized drive here, but I guess the principle works for things like USB pen drives. Read the tutorial here.

Powerful stepper motor board for the Raspberry Pi

The guys at Canadian company Roboteurs are currently running a Kickstarter campaign to fund their new stepper motor driver board – the SlushEngine. It looks like a stunning piece of kit and has the following features:

  • Controls up to 4 bi-polar stepper motors
  • Max 7A / motor
  • 9-35 V DC operating range
  • 1-128 microstepping capabilities
  • Integrated motion engine in stepper driver
  • 4 limit switch inputs
  • 4 general purpose industrial inputs
  • 4 general purpose industrial outputs (3A / 24V)
  • 8 additional logic level I/O
  • Thermistor temperature sensing
  • UEXT expansion connector
  • Raspberry Pi fused power source

It’s compatible with the B+, Pi 2 and A+ and looks like it could be a lot of fun to use, especially for projects where you absolutely, positively have to use powerful stepper motors – 7A per motor will certainly go a long way! The board comes with a simple-to-use Python library which lets you start up a motor with just three lines of Python. It’s great to see a company get the software right in addition to the hardware. It will also be completely open source, which is good to see.

The board is currently available to Earlybirds at $190 (Canadian Dollars) plus delivery, which works out at approximately £125 delivered. It’s quite expensive, but for those of you who have a specific application it could well be the board you’ve been looking for. Large power-hungry projects will certainly benefit from the engineering on display here. There’s also an $80 (£67-ish delivered) version to drive one stepper motor.

Take a look at the Kickstarter here if you’d like to find out more.