RoadTest: ACCESS:bit for micro:bit
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?: Kitronik STOP:bit - Traffic Light for BBC micro:bit, Kitronik LAMP:bit - Street Light for BBC micro:bit
What were the biggest problems encountered?: No documentation provided with kit; RoadTest-provided documentation was incorrect; correct documentation, once located, was illogically ordered (e.g. "step 4: do the programming; step 6: required setup to do the programming" 😕)
My 11 year-old Sam and I tested this product on an inclement Saturday afternoon. She is an accomplished micro:bit and Scratch developer thanks to her PLTW classes at school, as well as our own maker activities at home. I am an experienced maker, having spent many of my nights and weekends hacking on MCU or SBC-based projects since my purchase of an Arduino Diecimila in 2007. We were excited to receive this kit and see what we could do with it.
Our first RoadTest roadblock came when we realized that there were absolutely no instructions or other information included in the kit. We referred back to the RoadTest page, where we discovered a datasheet - but for a slightly different version of the product. The product depicted allowed the servo/gate to be mounted on either the left or right side of the PCB, whereas ours permitted only the left mounting position, with the right obstructed by a third AAA battery, not found in the original. Nothing about this was too severely different than the product we received, but it created a slight unease, which would increase as we progressed through our project.
The micro:bit affixes to the ACCESS:bit using 5x M3 nuts and bolts - a curious choice given the micro:bit's built-in edge connector; since the likelihood of the several thousand pounds of weight that this connection should bear being a factor in this project seems slim, my assumption is that the decision was made based on cost. Unfortunately my daughter found them quite fiddly and frustrating to work with, so I ended up doing most of the fastening - perhaps an edge connector would then be a better choice, depending on the intended audience - not to mention that it would allow the micro:bit to be far more easily reclaimed for other projects!
Still working from the "wrong" datasheet, we affixed the servo, connected it - purely based on experience with other similar micro-servos (no indication of positive/negative/signal was provided), and installed the batteries. Next, we moved on to the code.
The instructions showed a simple configuration of code blocks required to test the device, although this included custom blocks for the ACCESS:bit, which are not accessible by default. There was mention of a GitHub repository:
although neither my daughter nor I had ever added custom blocks via a GitHub repo, thus we were unsure how to proceed. I googled to see if perhaps someone else might have run into this issue with the ACCESS:bit before, and stumbled upon a product page showing the precise product we received (not the left "and" right/2AAA version) and an accurate datasheet to go with it! I was simultaneously overjoyed and frustrated by this discovery, since it answered many of the prior uncertainties (for example, which servo wire is which!), though unfortunately long after they were of any utility to us, having "made do" with the original datasheet provided.
These instructions still said "step 4: configure (inaccessible?) blocks as show", but, all the way at the bottom - literally the last thing on the entire sheet, after all of the steps required to use the kit - we eventually stumbled upon a "software" section, which mentioned how to add the Extension required to gain the missing blocks! So: step 4: use the blocks, step 6?: install them?? It was a needlessly long and frustrating experience getting the kit to the point where we could actually do anything with it, even with my decade-plus of experience in the space - I'm not sure if the kit is intended for young autodidacts, but the documentation falls far, far short if so. In a pedagogical setting, where the instructor has received significant training beyond the feeble datasheet, I can see those in the micro:bit demographic having success with it, but it's hard to see any other situation in which this kit might be usable, at least without significant confusion and frustration.
With the initial miserable experience out of the way, we honestly had a blast! After affixing the barrier - once we'd confirmed the down position via code blocks - Sam started coming up with all kinds of ideas for what we could do next. She recalled the micro:bit exercises we'd worked through a few years prior - animating the LEDs, making sounds, etc. - and immediately started applying them to the base example. By the time we were done playing, she had incorporated various emojis into the different states of the gate, plus new sounds, and a new mode where instead of pressing one button for up and the other for down, pressing both would allow the barrier to go up, wait sufficient time for a vehicle to pass, then move down again - all while displaying various symbols/emojis (e.g. "$" while down, indicating that payment is required, then to say "OK to go through" etc.) and emitting various sounds (such as a warning beep as the barrier started to move back down). It was really great to see how - after all our prior frustrations - she was able to absolutely rocket off into new realms of fun and creativity once we were finally up and running!
Bonus: when we went to find cars to test it with, we discovered that it's the perfect size for using with LEGO!!