Has use of the 12V pulse now been abandoned? I see no provision for it in the latest schematics.

Referring to the schematic in post #56 initially both outputs are Low. The 2V pulse generates a High output on pin5 and the motor runs from A to B. When that output goes Low again C2 pulls pins 8-12 Low briefly which makes pin9 High running the motor in the other direction.

 

Are you referring to my circuit in post #24?

NO!! I was not referencing that post.