Need indexing head software....

Group,

This has probably been discussed a million times on the list, but I
didn't pay attention because I didn't have a need until now.

I need a dos based stepper contol program for a single axis, an index
head for use on a CNC mill. Preferably, low cost or freeware. Needs
to have a method of sensing a switch closure from the machine's CNC
control to initiate rotation. Also, needs to have a method of
signaling back to the CNC controller when the rotary move is
completed. This type of communication between a CNC machine's
controller and an index head control is a common industry standard,
accomplished with 4 lines.

I own an older version of IndexerLPT which will do the job if I write
a frontend in Basic, but I'd prefer something that's already written
for this purpose.

Any ideas?

thanks,

Doug