Combining Stepper Movement and Dial Indicator Readout

Googling from this bit on the linked Instructables page:

Update: Igaging Origin Series use a Mitutoyo cable and output the Mitutoyo 52 bit datastream. The code and schematics below work with SPC Digimatic Calipers, Micrometers, Dial indicators, and Scales from both companies.

... I find:

with:

It looks like 10ms/bit. Plenty of time for an interrupt or some: