BackTrack CNC Darlington array update

[RobMcD101]

I have a BackTrack CNC conversion of a sherline mill which is using 3
Darlington array chips ( ULN2803A ). The problem is that this type
set up needs the software to generate the motor sequences, rather than
send step and direction signals. My software (MINC) is no longer
supported due to the programmer dying, and he had it locked up so
tight my hacker friends can't crack the "key disk". Does anyone have
a suggestion for an update for this system? I would prefer a nice
easy software fix, but I may have to update the stepper drivers to
zylotecs or similar. Cheaper is better. Someone suggested using L297
chips but I'm not an expert with electrons or wiring yet.

[NC Cams]

The ULN2803 is merely a package of Darlington transistors.

Anybody or nearly anybody can drive them with a computer or even push button switches. IT is the upstream logic (IE: MINC) that you need to hack so as to provide the proper logic between the "puter and the 2803's and that appears unlikely.

Wiring L297's is easy - download the application sheet. Writing the software that drives it is the hard part as is creating an interface between the computer and the power switching amps (IE the 2803"s).

If you're using a parallel port to drive, do a "parallel port interface" or "parallel port" search on the website. Follow the leads and you'll surely find something that is affordable....