The TB3 takes no part in this experiment, yet, it is just a convenient perch for the Arduino, the Bluetooth module and battery. The many cables are mainly redundant and are being used for another experiment.
The Arduino sketch is a beta supplied by Brian of eMotimo and the Bluetooth idea from a post on Timescapes by Chris from dp. Putting both together with a stepper drive is the resulting experiment I came up with, due in part to curiosity and because it has persistently rained here for most of June ;-((
This is a one axis test but can be extended to three axis control thanks to the ability of the TB3 to expose its Rx and Tx lines to the external port (via internal jumpers). The Bluetooth module can then be connected to the external port to send cnc Gcode instructions to its control board allowing "key framed" moves.
There are limitations to the number of instructions I can pass via the text file / phone combination, I am not sure if this is a function of the beta software or the phone app. but even so it allows more flexibility than A to B moves and without cables. Using the laptop there is no limitation, just the speed at which they can be executed again this may be a host terminal problem using local echo that can interfere with the next instruction, something to play with further.