Digital Music Programming II: Foot Pedal Machine

Here is a snapshot from the top of the pre-existing circuit board showing the input and output wires used to create the Foot Pedal Machine. Six wires were needed:

1. black wire: ground from the power supply to the BasicStamp.
2. red wire #1: +9 volts from the power supply.
3. red wire #2: +5 volts for MIDI output.
4. green wire: switch input into BasicStamp.
5. white wire: switch input into BasicStamp.
6. yellow wire: MIDI output data from the BasicStamp.

Here is a view of the reverse side of the circuit board. Notice the red, green and white wires which are passed through the circuit board using holes from unused components.

The following image shows a close up of the bottom of the circuit board with the feeds off of the two switches using the white and green wires. The wires were passed through to the top of the circuit board by hijacking a no-longer-needed capacitor's circuit holes. Notice the scratch marks near the center of the image were the pre-existing circuit board wiring was disconnected from the switch component.

The next picture shows some of the cuts needed on the bottom of the circuit board to isolate the used pieces of the board from the unused circuitry. This picture is near the MIDI output plug which is on the right.

Zoom in on the hijacking of the 220 Ohm resistors used for MIDI output. The yellow LED on the left was initially put into the circuit, but had to be removed because one of the LED connectors was connected to ground.

Here is a top view of the final wired circuit board along with the BasicStamp daughterboard connected to the feeder wires. Click on the image to get a full-scale image.

Another view of the original circuit board and the BasicStamp daughterboard. Click on the image to view the image in large format.

The final Foot Pedal Machine^TM box with the BasicStamp daughterboard included. Click for a larger image.

back view of the Foot Pedal Machine showing the +9 volt power supply AC adapter plug. Click for a larger image.