I have the following equipment ;
Modern PC running Windows 10
licensed copy Mach4
A Pokeys 57CNC
Creatity Ender 5 3d printer w/ single extruder head.

I have spent years learning LUA and the Mach4 system
Would like to use mach4 on the 3d printer.
What I would 'like' to do is connect and run the steppers and end switch's
directly from the Pokeys 57CNC. That part seems simple.
QUESTIONS ;
How could I  run a extruder step motor from mach4/pokeys. How could the extruder know how much filament to extrude.

How could I control the two heaters (base plate and extruder) from mach4/pokeys. There are several thermistors on the printer to feedback temperatures.

I am hoping if I cannot run it all from MAch4, I could use the Smoothie board for the heaters and extruders and  mach4/pokeys for the Steppers.

Existing control system. The original  board in the printer was replaced with a network smoothie board and Smoothieware software
After much trial and error it works but pain in the  ....

any hints , ideas greatly appreciated.  stay safe.

How could I  run a extruder step motor from mach4/pokeys. How could the extruder know how much filament to extrude.

Use a step dir spindle and control the motor with the S word, M3 for start, and M5 for stop.  See the Spindle tab in the configuration dialog.

How could I control the two heaters (base plate and extruder) from mach4/pokeys. There are several thermistors on the printer to feedback temperatures.

Bring the thermistors into a compatible ADC (analog input).  Then implement a heater control in the screen's PLC script or even a PMC ladder script. 

I am hoping if I cannot run it all from MAch4, I could use the Smoothie board for the heaters and extruders and  mach4/pokeys for the Steppers.

Mach can do it.

Steve