Introduction: PICAXE - Simple Programming Jig

This instructable outlines how to construct a simple programming jig that can be used to program PICAXE chips on a breadboard. It is advisable to build circuits on a breadboard first and having cobbled together various unreliable circuits to connect the programming jack to the breadboard when experimenting with PICAXE circuits, I finally got around to building a proper jig to do it reliably.

Step 1: Programming Jig Circuit

In the attached schematic you can see the simple circuit used for the programming jig. J1.1, J1.2 and J1.3 are the jumpers which go from the jig to your breadboard. J1, the programming jack is a 3.5mm stereo jack.

Note that in order for your circuit to operate reliably when it is running normally after programming, you need to have the 22K and 10K resistor combination connected to the Serial In pin or you need to connect a 100K resistor from the PICAXE Serial In pin to ground so that the Serial In pin is not floating. Otherwise the circuit may operate erratically.

Step 2: Parts List

1 - protoboard approx 2" x 2.75" (DX.com)
1 - 3.5mm stereo jack (Sparkfun PRT-08032)
3 - jumper wires (Sparkfun PRT-11026)
1 - 10K resistor
1 - 22K resistor
solder

Step 3: Programming Jack Pins

In the picture you can see the top view of the 3.5mm programming jack. This picture shows the location of the Gnd, Serial In and Serial Out pins on the jack.