Breakout board

anybody here know anything about parallel port lines and the breakout 5 axis boards. I was wondering if mach3 e-stop line is just another switch input signal. cause i know you have to enable 3-stop to get it to work. anyway I need 5 switches for the lowrider and there is 4 switches for the limit switch and a e-stop. any help would be great.


I think there are 5 lines dedicated for the input switch in the parallel port bus.

E stop should not use a digital switch. E stop should kill main power to the controller and router. This is to act as a safeguard. If it is a digital input on the board and for some reason the board errors out, then the E stop could fail to stop the machine.

there are 5 sw lines the mach3 configuration configures the sw for. I am just wondering if the lines are references for switch signal.

Not sure, I haven’t done anything with Mach3. I’m sure there is a way as almost any input can be used as a switch input with enough work.

that’s what i’m thinking. I’ll investigate more or just hook up and see if it see’s the switch. thanks for getting back thanks for the help. found a schematic of the printer port. shows 5 lines that are exactly the same through put.

one of them call e-stop. I guess we are right i will bread board it and see. I update you whether it will work or not. later
and also shows this.

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There are alternatives to lower the number of inputs you need as well. For instance grblesp does autosquaring with only one switch input per axis. It does this by moving both motors until one of the two switches is triggered. Then moves only one motor at a time to square the machine.

Just a thought in case your experiment doesn’t turn out.

how do I go about doing that with this card. how do I find a grblesp

Grblesp is firmware, like marlin. It is a grbl fork designed to run on an esp32. That said to do the same sequence in Marlin you would need to modify the marlin squaring code. If your using Linux cnc (witch is what I assumed since that is normaly where I see Mach3 parallel port interfaces), it should be a fairly easy modification in the code.