Convert a cheap Bluetooth Numeric Keypad into a Pageturn Stompbox

[Marshall Arts]

The topic says it all. This is (obviously) not to show off any special skills, I just wanted to quickly build something really cheap and did not want to pay 60 bucks or more on an Airturn or Blueturn. Here is how I did it, in case somebody is looking for something similar, this will save you a lot of time for reverse engineering the keypad logic...

Start with this keypad (only the packaging is left...):


Remove the keypad from the main PCB (you can slide it out or simply cut the transparent "cable")



Cut off the plastic enclosure below the battery compartment (already glued in the enclosure and wired in the picture)


Solder wires to the PCB to the connections A3, A6, B5, B10, B15. I chose the following colours:
A3=White
A6=Brown
B5=Yellow
B10=Grey
B15=Orange

For the offboard wiring, the following connections send the corresponding keypress:

A6-B15="6/go right" (brown/orange in my build)
A6-B5="4/go left" (Brown/yellow in my build)
A3-B10="Bluetooth connect" (white/grey in my build)
A3-B5="Toogle Num Lock" (white/yellow in my build)

The last two are only needed to bind the pedal to a new tablet/notebook/mobile phone or to change to cursor mode, should the device ever come up with num-lock activated (it actually has not so far...)

The back lid allows for access to the batteries and the on/off switch:


The front side could not be more "Quick and Dirty DIY":

[sjaustin]

Cool project!

[gordo]

Ahhh, now how to fit it into the Eoo3...