From memory there was some comment that it used ascii. From what I can gather it uses the signals that many dro sensors put out and can even cope with pure quadrature outputs which are just pulse trains, 2 in antiphase so that direction can be sensed. It may well be able to cope with ascii outputs from sensors as well as I believe some do that.
What isn't clear when I look at the site is what does what. For instance it states that a board can be easily converted to use quadrature but from what I can see no signs of how. It shouldn't be difficult to handle this in a micro because it's just a case of counting pulses and noting which one changes first so that direction can be detected. As for instance this is how car steering angles are detected. Linear motion is no different.
Being fair to the man who has done it supporting something like this can be pretty onerous for a one man band and the mixed signal board seems to be pretty new.
The unit that has to be built or bought may well use ascii to transmit data to the tablet via bluetooth but that's not really relevant because if some one dug deeply into a one piece commercial unit it might do the same to communicate with the display. All most certainly if it used a touch screen and probably in other cases as well. I have hand cranked simple displays in the past but there comes a point where it's easier to tell a display unit to do it rather than set dots or segments etc.
Bluetooth may be a weakness, noise immunity, but it seems some have converted to serial, possibly even usb. Some are using USB cable for sensor leads as they are shielded and also the connectors at times.
John
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