Stepper , servo, inverters

Hello people,

I am new to this group. I want to control a 4-axis PKM and intend to
use EMC for that. it uses 4 Eurodrive-SEW inverters and AC-motors
with incremental encoders. The inverters need, to work, a process data
object which contains 3 bytes (control, desired vel, desired pos) and
returns more 3 bytes (it is balanced)(status, actual vel, actual pos)
at 500 kbits/s trough Fieldbus - Interbus.
I need realtime control and 4 axis interpolation. Using EMC i will
make a driver which read output from parport for each axis (dir/step)
and converts it to SEW process data object. This is my second option.

Because I also have an ISA/Interbus board from Phoenix Contact
installed on my PC. I use a linux interface for this board and have a
utility lib in C for managing this board. My question is where to put
it into EMC code (I want to use all EMC code for interpolation, PID,
encoder-feedback, etc. But i dont want a dir/step interface, this code
i didn´t find???). Or even for servo, Does EMC send dir/step to
parport? If not dir/step, is it PWM?

Can anyone help?

Thanks,

Mateus HFA