Crank Counter with micro:bit

I’ve got a new guide up in Brown Dog Gadgets Project Database. This time we’re using the micro:bit along with a 7 Segment Display and a LEGO-based crank circuit. I call it the Crank Counter.

We create these (free) resources in the hopes that viewers like you support our efforts by purchasing components from Brown Dog Gadgets because hey, that keeps the free resources flowing. Thank you for your support!

Typically the build guides are not a step-by-step LEGO building guide, but they don’t need to be. LEGO should be open-ended building, and we want to encourage that. Even the circuit layout with Maker Tape doesn’t need to be precise. The components must be connected properly, but where you place them, length of tape used, etc. is less important. Building a functioning circuit is the goal. (Things that need to be more “exact” like the crank connections, are called out.)

I typically try to explain the code a bit and cover a few other basic concepts that relate to the project. Some are more advanced than others, but we try to simplify and not overwhelm.

Oh, you might be wondering if we can made a version of this that counts down as well as up depending on the direction you turn the crank, and yes, that’s possible, and it’s in the works. :)


Blink Without Pause on the micro:bit

If you’ve ever used an Arduino there’s a good chance you started with the Blink sketch, which is a great introduction to programming a physical computing device where you can see the outcome in the form a blinking LED. As you learn more and things get complex, you discover that using the delay statement in your code is not ideal as it prevents the code from continually running, so you can’t properly capture input to your microcontroller. There’s more over at the Blink Without Delay tutorial on this topic.

I’ve been doing a lot with the micro:bit lately, and my quick searches gave no equivalent for Blink Without Delay so I created Blink Without Pause.

The tutorial starts with micro:bit code for Blink With Pause (which is really just Blink) and then Blink Without Pause so you can compare the two.

For a real-world example there are two more, Blink With Pause With Button and then Blink Without Pause With Button which should clearly illustrate the value of not using pause if your code needs to do other things.

Oh, if you’re wondering where the micro:bit is in the illustrations above… it’s not there! The diagrams show the Bit Board that Brown Dog Gadgets will be releasing this fall as part of a Kickstarter campaign. Follow on Twitter, Instagram, or Facebook to see some of the other projects we’ve been doing and find out when the campaign launches.


Reprogramming an ATtiny85 Blink/Fade Board

A few years ago I helped Josh with the code for the Blink/Fade Board that Brown Dog Gadgets has in their Crazy Circuits kit.

This is a simple board that comes preprogrammed to do a few specific things, with the idea that you can start using it even if you don’t know how to program or upload code to a controller. Besides power in, ground, and reset, there are five GPIO pins that we can use:

  • Pin 0: fades in and out
  • Pin 1: heartbeat
  • Pin 2: twinkles randomly
  • Pin 3: blinks on and off
  • Pin 4: blinks off and on (alternates with Pin 3)

We’ve always said that expert users could reprogram it to do anything an ATtiny85 can do, but we never had a guide… until now. Courtesy of Brown Dog Gadgets here’s the Guide to Reprogramming a Blink/Fade Board!

We’re using the Arduino IDE along with a SparkFun Tiny AVR Programmer to do the heavy lifting… You’ll also need to build a little LEGO jig with some Maker Tape and Crazy Circuits components and some Dupont jumper wires to string it all together.

After I reprogrammed the board I popped it out of the programming jig and popped it into a simple circuit to control the brightness of an LED with a potentiometer. You can’t do too much with an ATtiny85 but it does have a few inputs & outputs and you can even control a NeoPixel strip with it! (A guide for that will be coming soon.)

Like most of the guides we do there are some nice diagrams and downloadable PDF files with more/helpful info. Here’s one covering the reprogramming aspect of the guide…

And here’s one that shows using the reprogrammed board in the LED/potentiometer circuit. (The code for BFDimmer is available.)

I’ve been doing my best to keep cranking out fun and educational guides for projects. While a lot of them have been focused on simple circuits or Arduino-based things, we’ll be expanding into Micro:bit projects in the coming weeks, which has definitely been interesting.


Manual Crankable Larson Scanner

The most recent fun project at Brown Dog Gadgets is our take on the classic Larson Scanner. EMSL has an awesome kit, and many people who have experimented with an Arduino and LEDs have made a breadboard version.

Well, Josh and I made a LEGO version using Crazy Circuits parts, and instead of a microncontroller it’s controlled by a hand crank! Yeah, it’s an Analog, Hand-Cranked, LEGO-Based, Crazy Circuits Larson Scanner.

As with all of our projects, the instructions, files, templates and all that are available for free. Check it out! You can certainly use other components besides Crazy Circuits and Maker Tape for this, but as always, getting parts from us (or a reseller) ensures we can keep producing open source educational content and curriculum. And yes, schools, teachers, maker clubs, and other use these resources, and we incorporate their feedback into new designs and projects.

There’s a bit of an explanation about the cylinder and “coding” as it were, in the instructions. While this is a simple & fun project, you can expand upon the basic concept to talk about more advanced concepts. That’s pretty much our goal with these things.

Josh had a lot of fun making the video for this one, though I’ve heard that stock music way too many times in other videos! ;)

Perfect for your Knight Industries Two Thousand or Cylon!


Crank Activated LEGO Circuits

The latest project for Brown Dog Gadgets is a LEGO-based, crank-activated circuit. This is a simple build that uses LEGO along with Maker Tape to allow a rotating cylinder to close a circuit.

The trick here is that Maker Tape is not just conductive, but it’s strong, and can be stretched just a bit against the cylinder to provide good electrical contact. Besides a few LEGO bricks on a baseplate we’ve got some round LEGO pieces for the cylinder, two bricks with holes, a long and short axle, and a beam with axle holes to make the handle. Overall, pretty simple.

This is one of those projects which really highlights what Maker Tape can do. There really isn’t an easy or reliable way to do this with wire, or with copper foil tape.

The video below shows the circuit in action, and if you want more, we also showed it off during one of our live video streams that we do each week.

As always, get the full details of this build on the Brown Dog Gadgets Project Site. And yes, we’ve got a lot more fun coming with crank activated circuits!