My snap:bit

Basically I wanted to extend the sensors and other components of my son's Hot Wires kit to be used with my daughter's micro:bit. There are a few ways to do this: SCJW10 Elenco Snap to Pin Set, Snap to Pi Snap Circuit Kit, or snap:bit. All are good, all are valid, but I wanted to go my own way and make vs buy.

To do this I needed a donor component shell to keep the look as factory as possible. I selected the U6 Recording IC from the original kit and purchased from eBay (piedwoodpecker £1.75 + £0.99 Postage). I wanted this case because it has three top side snap connectors and four bottom side snap connectors, which I though made a good pairing to the three main sensor pins (0, 1, 2) and two pairs of power inputs allowing for a split 3V3 and 5V, if required.

I decided that a 3-wire and 4-wire arrangement would suit most requirements hence settled on 3-wire inputs and 4-wire inputs to jumper wires. In keeping with the 3-wire, 4-wire and 5-wire jumper kits available from The Pi Hut I settled on Yellow, Red, Black and Orange, Blue, Red, Black colours (102923, 102924 and 102925 £1 each + £2.99 Postage). NB I split a couple of packs (2x 3 wire and 1x 5 wire) to get the colours and group the wires in 3 and 3 + 1 arrangement at the loose ends.

The case is rather tricky to open with hard plastic pins around. I found a credit card sanded on the edge worked as a prying tool. NB I lost a couple of the clips in the process.

With the case open the IC board is easy to desolder from the seven terminals with no physical retention. I drilled two holes in alignment with the seven connectors to keep neat. Assembly consisted of stripping each jumper wire and soldering to the chosen terminal. I choose a clockwise arrangement.

Connector 1 = Orange

Connector 2 = Yellow

Connector 3 = Blue

Connector 4 = Red #1

Connector 5 = Red #2

Connector 6 = Black #1

Connector 7 = Black #2

1, 3, 5 and 7 are top and bottom 4-wire (3 + 1) jumper

2, 4 and 6 are top 3-wire jumper

I added a little bit of heat shrink (unshrunk) for through-hole protection and closed the lid. My design aligns with the Keyestudio KS0360 shield/carrier board and the micro:bit, hence, groups the jumper wires in 3-wire (primary) and 3 + 1 wire groups (primary and offset secondary inputs), which aligns to the Pin 0, Pin 1, and Pin 2 on the Keyestudio board. It works great and is very flexible allowing for 3V3 and 5V rails primary and secondary inputs/outputs. I didn't change the original wire lengths, but I noticed an added benefit that the top set finish slight longer, so sit above the second set, which is nice. Less than a tenner to make. What's not to like?

PS I removed the U6 marking from the top of the plastic by flat sanding on the bench with very fine sandpaper.