ACCESS:bit for micro:bit - Review

Table of contents

RoadTest: ACCESS:bit for micro:bit

Author: rancell

Creation date: 16 Jul 2020

Evaluation Type: Development Boards & Tools

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: Other products in the Kitronik family include the STOP:bit and LAMP:bit and :MOVE mini.

What were the biggest problems encountered?: No information provided in set, small bolts and screws.

Detailed Review:

Today was pouring with rain so it was the perfect time to road test the ACCESS:bit with three bored children (4, 7 and 8). The ACCESS:bit is a expansion board make by Kitronik for the micro:bit that simulates an access barrier. At a technical level, it is adds sound (buzzer), motion (180 degree servo motor) and power supply (3✕AAA batteries) to the micro:bit. I've used a number of Kitronik parts before as well as other micro:bit expansion sets. The ACCESS:bit is priced about the same as a micro:bit, which makes it an affordable option.

What I received was the ACCESS:bit components in a bag and a micro:bit (board only) to use with it. The ACCESS:bit doesn't come with a micro:bit in the pack. Well, actually I received two ACCESS:bits and micro:bits in what I assume was a shipping mix up. It worked out well, as then I could do the road test without the kids fighting over who was using the board! I provided a small screwdriver, USB cable and batteries.

No instruction were provided with the pack, so I went online to look for them. The Kitronik product page has a two page PDF with assembly instructions and a basic program to use. It also has a short video (mostly for marketing purposes) and a link to two lesson plans. This material was of a very high quality and I printed out the PDF instructions for the kids to follow. I imagine that no instructions were included with the pack to keep the price down, but it probably should have a sticker on the bag with the URL to these instructions as other kits often do.

Assembly involves bolting the micro:bit to the ACCESS:bit board and screwing the servo on. The bolts and screws are very small and while the kids did have a bit of difficulty they did find it fun to assemble. The bolts hold the micro:bit very strongly, but the downside is it makes it hard to remove the micro:bit if you want to do other projects. Alternatively you can use crocodile clips to connect the boards together. I've found the best micro:bit accessories use an edge connector socket and I wonder why Kitronik doesn't use these on all their products (cost saving?). The last part of assembly is attaching the barrier arm to the servo which is a push fit (screw provided for a firmer attachment if desired). The assembly was suitable for this age group both in complexity and time taken and made the project more engaging.

One thing I'm always interested in with expansion boards is how the battery supply works. Batteries are expensive and wasteful, so I try to minimise their use where possible. The micro:bit functions well over the USB cable, so I like batteries to be an optional extra. I noted the following:

• The batteries are required to make the ACCESS:bit balance.
• There is a small power switch to enable the battery supply, but it's easy to not notice if it's been left on (no power indicator LED).
• It works well with 1.2V NiMH batteries, so that's good for reducing battery waste (especially if left on).
• The buzzer works when the micro:bit is powered over USB, but the servo motor does not (the micro:bit does have sufficient output to power a servo by itself).

Anyone familiar with programming a micro:bit will have no trouble using the ACCESS:bit. Kitronik has provided a MakeCode extension that provides two new blocks to use. "Move barrier" allows you to move the barrier up or down and "Sound" allows you to easily beep the buzzer. This functionality can also be done by using standard low-level MakeCode blocks and this allows a beginner/advanced coder usage of this product. The Kitronik lesson plans take advantage of this. The kids copied the basic example program, downloaded it to the ACCESS:bits and had a lot of fun playing with them and toy cars. I think the design of this product is very appealing to children.

The next step is where the learning value of a product like this comes in. How can you modify the ACCESS:bit to have your own behaviours? The children did the following:

• Changes the number of beeps the buzzers made.
• Used the micro:bit LEDs to show their own signals when the arm moved (hearts, animations).
• Replaced the basic beeps on the buzzer with melodies.

In conclusion I would recommend this product for those who are using micro:bits and want a simple project. The product is affordable and appealing to the age group I tried it on (~8 year olds). The packaging lacks information suitable for them to self assemble, but it can be easily found online. Due to the small sizes of the bolts and screws help is required from an adult. The board is sufficiently simple for children to understand how it works and easily program it to do their own behaviours. Nice work Kitronik and thanks Element 14 for sending me this to road test!