home switches

i am fairly new to the cnc world. i purchased a “no name” cnc that operated on linuxcnc. i am fairly happy with it eexcept it does not have home switches (if i have a tool path that requires different cuts with different bits it can be quite a problem). so i went out and purchased switches (inductive limit switch). installed them. did not yet wire them because i am not certain how to. called someone who knows how to. he does not know linux cnc. cannot help me to configure in linux cnc.

now everyone is telling me to change over to mach4. i did. bought the software and the usb/db25 dongle (from practicle peripherals). can’t get it to work. now telling me to change computers!


all i want is for the switches to work in linuxcnc. but i cannot find anyone to help me locally (montreal canada) or by remote access ( i am willing to pay) to make this work. any suggestions?


I wish I could help. I have not had any experience with linux cnc though. Hopefully someone can jump in and help. I suggest putting up a few pictures of the control board to see if anyone has used one. Some of the machines can come with some nasty boards.

As for changing software and computers…lame. You can skip it all together and use a LCD, there is no magic in the software it feeds very basic coordinates to the board, that does all the work. The software literally just sends one line of commands ( a few characters) at a time as the buffer empties. I get very annoyed when people think different control software is somehow “Magic” I use a $12 LCD, no need for $400 control software. If you have Linux cnc running, no need to switch, and adding limits switches should be easy. Chances are you just need to plug them in and incorporate them into your CAM. You might not have to even make a change.

As a long time hater of windows, I can agree with the hate for mach4. I don’t know much about linuxcnc though. Didnt the project fork and has a new name?

I’ve only heard of one linux cnc user here. The guy (Tom?) that wrote in the digital machinist magazine. Is there a forum where those guys frequent that might be able to help?

Ugh. You don’t need a new computer.

LinuxCNC. I use it. I like it.

The switches should be wired Normally Closed(1). For the sake of simplicity, I would wire them all in series. Connect them to an input line on your driver board or breakout board.

Then it’s as simple as running the stepconf wizard in the LinuxCNC menu (I use Linux, it’s there… If you’re on windows… Dunno?)

There’s one menu page where you input which parallel port line does what function. There’s a bunch of outputs which should be set up for X dir, X step, etc etc etc. Off on the right there’s inputs. Set whatever parallel port pin is appropriate (check your documentation for your driver board or breakout board) to “all homes”.

That should do it.

If this doesn’t help, I’ll be re-setting up my own linuxCNC box today or tomorrow and can grab screenshots if you’d like.


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