This is a DRAFT write up illustrating how the Bantam Tools mill is used in the prototype development process at Lectrify. This page is not linked from our main web site but can be accessed directly. Please do not share the link without permission from diego@lectrify.it
It starts with a market need
The bit: booster was designed to be multi-purpose add-on board for the micro:bit enabling both science experiments and robotics projects.
At $35 it is highly competitive as a robotics/science add-on but still adds significant cost to a micro:bit project.
What was the simplest board we could design that could sell for less that $10 and still add value to the micro:bit in the classroom?
the Bit:lab - Sensor only board
They key design constraints were that it had to be low cost and useful.
Perhaps the two biggest issues with the micro:bit are:
that the battery pack provided with the Go kit isn’t connected to the board.
Accessing the pins on the edge of the board require alligator clips or banana plugs (and there’s only one power and ground pin)
First Prototype: Bit:Lab
The first prototype was to test feasibility and utility of a fully stripped down add-on. Key features include:
Screw down connection for the board
Onboard 2032 battery (that can be replaced while still screwed down)
2 Dupont Connectors for external sensors.
1 Grove connector using ports 1 & 2
Piezo Buzzer using port 0.
Back of board with Grove connector and two angled headers visible. NOTE: There is a missing wire for connecting pin 2 to the headers.
Front of board showing how it is fully hidden behind the micro:bit but battery is still accessible to be replaced once screwed down.
Parts list:
Single Sided FR-1
Screw down terminals (can use either 6-24 screws and nuts as pictured or Hex Standoffs like these from Mouser)
Grove Edge connector - Mouser Link
Battery Holder - Mouser Link
Right Angled Headers - Jameco Link
SMT On/Off Switch - Jameco Link