Mitutoyo Linear Scale AT715 signal format?

Does anyone happen to know the signal format for Mitutoyo Linear
Scales, series AT715?
I want to interface one to a microcontroller such as a PIC and need
the pinout and signal information.
These scales are intended to be exclusively connected to Mitutoyos KA
Counters.
These scales are Absolute reading units and I'm assuming they spit out
a continuous stream of serial data to indicate current position.
Or they send data upon a request, or???
Thanks!
Tom M.