Hello Friends
On my lathe build I have a drama with the spindle index input back to Mach3.
I'm using 2 Parallel port's one for for inputs and one for outputs, all other functions are fine except spindle index feedback.
I have a disk with a slot cut into it which passes through an opto switch, the disk is fixed on the lathe spindle and is used to measure rpm of the spindle. The BOB has individual leds and without fail the led corresponding to the index flashes every time that notch passes the Opto, Even if you go to diagnostic screen of Mach3 and turn the spindle by hand you will activate the light registering the notch passing the opto switch in the index box.
Now what I find screwy a bit it will not register every time on the Mach3 Diagnostic screen at speed , but I have been told it has to do with the screen refresh rates?
Anyhow the problem is I cannot get accurate low RPM take a figure say 200rpm and below if I do not set my Index Debounce to over 80, but that will give no figures over 300 odd. Max RPM at 2000 will work only if I change the Index debounce figure to 8 but will not give me a true reading for anything under 1500rpm.
The BOB led picks up every pulse but for some reason the readings in Mach are just everywhere.
Any Ideas?

Katoh