micro:pegs

What do micro:pegs do?


In schools, two of the most commonly used small board computers are the Crumble and the micro:bit. 

Both boards incorporate 4mm holes which serve as terminals for connecting external components. 


To simplify the connection of wires to the terminals I have invented a simple little device named the micro:peg

The LED in the picture on the right is connected to Pin 0 and GND using micro:pegs.


The two pictures above show crocodile clips connected to the 4 mm terminal holes on a Crumble and a micro:bit.

How do micro:pegs work?

About a centimetre of insulation is stripped from the end of the wire to be connected. About half of the bare end of the wire is pushed down though the 4 mm terminal hole and folded back on itself. A micro:peg is then pushed into the hole to hold the wire firmly in place. 

Multi strand wire works best but for single strand wire, or when connecting unwired components, the groove in the micro:peg can be lined up with the wire to make space for it next to the peg.


Removing the micro:peg releases the wire. 


Because the connections made with micro:pegs are more secure than crocodile clips, the teacher can make up the circuits before the lesson and hand them out to the children to use.

If the children start to make a circuit but do not finish in time, their circuits can be collected in and handed back to them to complete during another lesson.


See the video demo below.


The video above shows a 9 year old child giving a Mark 1 micro:peg demonstration.


The images below show a wire connected to the GND pin using a Mark 2 micro:peg.

micro:pegs can be printed in a range of colours to help children to connect wires to the correct terminals. 

Red and black pegs help to clarify the positive and negative terminals.

What problems are micro:pegs designed to eliminate?

A standard method of connecting components is to use croc to croc leads. These work well but when using them in my lessons I have experienced the following issues:

The picture above shows three components sharing the same GND terminal.

How easy are they to use?

I have used micro:pegs extensively with children in National Curriculum Years 4 to 6 (8 to 11 year olds). With a little bit of practice they found it much easier to attach and detach wires from the 4mm terminals using the pegs than they did using crocodile clips as demonstrated in the video above.

Some of the advantages to be gained from using the pegs are as follows:

Compare the two burglar alarm circuits below. They use exactly the same components and yet the one on the left using micro:pegs is much easier to make and to understand.

Pressure pad burglar sensor and alarm circuit 

connected to a micro:bit with micro:pegs.

The same components

connected to a micro:bit using croc to croc leads.


Manufacture and distribution

I have not sought to patent my invention. I am offering micro:pegs to commercial companies to make use of as they wish. My interest is to see my invention used in schools to make physical computing easier, particularly for children in primary schools.

Should a company wish to mass produce micro:pegs for large scale distribution then all I ask in return is that the invention is attributed to myself, Graham Hastings.



There are two models of micro:peg. The Mark 1 pegs illustrated in blue on the left below are designed for components with 'bare legs' or for single strand wire. They create a more secure, semi-permenant connection.

The Mark 2 pegs illustrated in orange on the right below are designed for multi-strand wire and are much simpler to use. You simply press them into the hole to trap the multi-strand wire. To disconnect them simply turn the micro:bit over and pop them out.


I have made two Tynkercad files available for export as .stl files ready for 3D printing.

The choice of colours is your own to make but red and black help to clarify positive and negative/GND terminals.

Mark 1    Use for a more secure semi-permanent connection.    https://www.tinkercad.com/things/j1LLddzHfJ2

Mark 2     Use for quick more temporary connection.    https://www.tinkercad.com/things/8XKPSXZqh8H-micropegmk2       


Mark 1 Mark 2

I leave the pegs attached after printing and snap them off as needed.

Mark 1 micro:pegs can be used to attach components with 'bare legs'.


Graham Hastings is Head of Computing at St John's College School,

Cambridge, 

UK.



Email: hasklass@gmail.com

5/4/2023