New Pc Parallel port jitter

[Jordan T]

Hello there,
I have a 2 axis stepper system which runs fine off an older model PC parallel port but gives steppers a poor erratic motion when controlled from a new PC.

a cnc4pc output buffer board and G1G breakout board are used in conjunction with G201 stepper drivers. Have installed motors spindle encoder Etc to a Hafco AL960 toolroom lathe, so do not want to use an external motion controller.

Both computers have the same setup in the BIOS and Mach 3

Can anyone help me understand what changes I could make to get a better signal from my Newer PCs printer port.

Regards, Jordan

[ger21]

http://www.machsupport.com/downloads...timization.txt