Prog-03 Programming Adapter
The Prog-03 programming adapter is specifically designed to minimize the breadboard connections needed to program all current PICAXE 8-, 14-, and 20-pin processors. (However, the Prog-03 can also easily be used to program other PICAXE processors as well.) The following photo shows a complete "Hello World" circuit implemented with the Prog-03 adapter and a PICAXE-08M processor. As you can see, the required connections are minimal. The Prog-03 directly connects to the 08M's Serial Out and Ground Pins, and also completes the Ground connection to the breadboard's Ground rail via a 2-pin header, which isn't visible because it's underneath the stereo adapter. Only three additional jumpers are required; one is needed to connect the 08M's +V pin to the breadboard's power rail, and two are needed to connect the 08M's Serial In pin to the corresponding Prog-03 pin. The resistorized LED in the circuit is connected between the 08M's Serial Out line and Ground.
There are three important points to note about using the Prog-03 adapter:
First, it requires that the power and ground pins in the power rails are offset from (i.e., not in line with) the rows of pins in the main portion of the breadboard. All 400-point breadboards that I have seen are constructed this way. However, larger breadboards are not, and therefore cannot be used with the Prog-03 adapter.
Second, the breadboard must be oriented as shown in the above photo (i.e., with its power rails below its ground rails).
Third, if you want to run a program without the Prog-03 being connected, it's necessary to re-establish the ground connection for the PICAXE processor, and to tie the processor's Serial In line to ground (e.g., with a 100k resistor).