Anyone good with phase angles?

This dead horse has been beaten enough, but I got sucked back into it after a couple of years of (successfully) ignoring it.

The OLD iGaging Absolute scales use a 52 bit data word transmitted every 0.1 seconds. That’s a 10Hz refresh rate, so they are pathetically slow for what we want. But there are people out there that still have them. Anyway, the data word contains a 25 bit data segment that encodes the actual position. That 25 bit segment has 3 data words in it, the Coarse track, the Medium track, and the Fine track. The bit sizes are 8 bit, 8 bit, and 9 bit, respectively.
Through observation and a little math, it’s been found the total length of the Coarse track length (or period) is 1310.72mm with a frequency of 1, and the Medium track has a frequency of 8, and the Fine track has a frequency of 256. The phase offsets are not yet known, but are being worked on. (If you don’t feel like doing the math, those numbers give a resolution of 0.01mm, which is what iGaging claims).
Anyway, I’m not all that good with figuring out how to do the phase angle math for the 3 phase angles, and I’d appreciate any help anyone can offer!

FYI, I know this will never be incorporated into the controller firmware. These scales are WAY too slow in their response time. Custom firmware can be written (and I probably will write it for a friend). But it’s great to be able to support as many scales as possible!

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