[_jools_]

hi

I'm building a rotary encoder using optical sensors for spindle speed feedback to linux CNC but need help with wiring it and resistors needed. I am going to have 50 slots and channels a b z. My spindle tops out at 2500 so the max frequency would be (50 x 4 x 2500)/60 = 8.33khz (if i'm correct).

1 The MX3660 says the inputs are 12v sourcing but the output from the photo sensors is 5v. Would this matter? if so is there a way to amplify the signal? (as an aside my home switches work ok with it and they read -10.5 to 10.5v when triggered.

2: if it does matter could I run the emmiter side on 5v then have the collector side take a wire direct from the parrallel port @3v and then run it straight to the ground of the parallel port? Linux cnc has a function where you can measure pin signals and if I ground out the correct pin it switches between true and false. I wondered if there are reasons why this couldn't be done?

Please help with advice as i'm fairly stuck.

Jools

[Al_The_Man]

Why re-invent the wheel, if using photo devices anything over around 100p.rev requires a Moiré effect reading head.
Also if just measuring RPM, you don't need a quadrature encoder unless you have positioning and direction in mind.
.What do you intend doing with the signal?
Also you need a system that can read the sensor without interrupt in a constant manner.
Al.

[_jools_]

Why re-invent the wheel, if using photo devices anything over around 100p.rev requires a Moiré effect reading head.
Whats this? The optical sensor is of the interupptor style sensing though a slotted disk?

Also if just measuring RPM, you don't need a quadrature encoder unless you have positioning and direction in mind.
.What do you intend doing with the signal?
rigid tapping

Also you need a system that can read the sensor without interrupt in a constant manner.
What kind of system would this be? do you have any diagrams or links that could instruct me?


Al.

Jools

[Al_The_Man]

What kind of system would this be? do you have any diagrams or links that could instruct me?

Rigid tapping usually requires a higher resolution that this.
I don't use Linux.
Max.