hi i am new to all of this and i had a post or read one some where about going into ports and pins to set spindle speeds to coendside with dro on mach i am using a tach to find out where i am at any help would be appreciated thanks bob b please email me at rcbarton@ verizon.net 

You will need an index pulse fed into Mach. A slotted disc with an optical switch works well, I have used OpTek OPB 916B optos to good effect.
Hood

i am totaly lost  please explain in laymans i am not very pc savy sorry

To get the actual speed to show in Mach you need to send Mach a single pulse once every revolution of the spindle. If you mount a disc with a slot in it onto the top/end of the spindle then you can use an optical switch to send that signal to Mach.
Probably best to say what kind of machine you have though as if its something like a router with a dremel for a spindle then its not going to be an easy thing to do.
Hood

Hi Bob,     Im also new to mach and CNC in general so i probly cant offer much advice,but,if you could explain your setup and what your trying to achive in more detail,im sure theres someone here that can help.

what kind of spindle are you useing? does it have multiple gear ratios? are you useing step/dir or PWM to control the speed?

the more detail you can give the better.


regards
Simon

well my nm145 suppost to have an 8 poll motor on it and when i punch spindle speeds in it is not even close to what i punch in is thier a way to set those parameters on ports and pins

You will have to give us more info on your spindle and how it is controlled. Do you have any documentation that you can attach?
Hood

BOB       i just had a look on the novakon website for the NM145 and it does mention that there can be fluctuations in the spindle rpm by up to 10% and on a 6000 rpm spindle that could be as much as 600 rpm diffrnce bettween the rpm you ask for and the rpm you get.  there is a tab called "spindle setup" in ports and pins. I THINK your machine uses PWM to control speed. I have never played around with PWM so i couldnt tell you how to fine tune it. mine uses step/dir.



regards
Simon

ok here is another dilema i got lic. for new fangled wizards it said to copy and paste into directory what do they mean by directory be more specific

sorry to be a pain guys i guess an old hands on machinist should have just stayed that and bought a bridgeport because this is way over my head thought i could learn it