I need super basic Help with Hardware choices

so with the using one of the mesa ethernet options gives you some room to change platforms.

It will work with a RPI4 and most desktops that have good latency.
some options for mesa ethernet are
store.mesanet.com/index.php?route=produc...t_id=311&search=7I96
store.mesanet.com/index.php?route=produc..._id=290&search=7i76e

The 7196 has 11 inputs and 6 outputs (there are expansion cards for future upgrades.)
And the 7i76e has 32 inputs and 16 outputs
Both can drive 5 stepper or servo motors.

Take a look at the manual for a second see page 10 in the doc (page 5 as written on the paper)
You will see it has headers labeled step 0 step 1 step 2 step 3 step 4, ect
If you zoom in you will see the pins are labeled 5V, dir0+, dir0-, step0+, step0-, gnd
www.mesanet.com/pdf/parallel/7i96man.pdf
Now if you look at your motor driver
www.jmc-motor.com/product/954.html
and look at the Connections to Differential Signal
you will see pulse signal, direction and enable.
You would hook the step from the mesa to the pulse on the driver
and dir from the mesa to the direction pins on the driver.
For the enable you would hook all the driver enable pins together and use one of the outputs found at the bottom of the mesa board.

So as long as you have power being fed to your motors and the mesa board
and you hook everything up then you will be able to move your motors around.

both mesa cards above will do a standard cnc machine but if one wants to start adding a bunch of extra features and sensors or switches the one with more IO will be better. but if not needed could be unnecessary

other things you should have are limit/home switches.
A big E stop button that can be slammed to quickly stop the machine. (this is a must trying to hit a key on a keyboard while something is trying to break itself or smoking a motor sucks!)
Good wires that can take vibrations. (this is a luxury but its nice to not chase down sporadic issue only to find a wire snapped inside the insulation and the issues only happens once every few months and you go crazy changing switches and connector ends to forget this can happen....)
maybe a few buttons to make hardkey cycle start and pause and tool change confirm. a few relays to turn on dust collection/ coolant.

Aaroncnc wrote: so with the using one of the mesa ethernet options gives you some room to change platforms.

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Take a look at the manual for a second see page 10 in the doc (page 5 as written on the paper)
You will see it has headers labeled step 0 step 1 step 2 step 3 step 4, ect

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other things you should have are limit/home switches.
A big E stop button that can be slammed to quickly stop the machine. (this is a must trying to hit a key on a keyboard while something is trying to break itself or smoking a motor sucks!)
(…)

Thanks, this is very helpful.

Yes, endstops and emergency button are a must and planned. Relays for all the good stuff are definitely planned down the line, especially after I managed to ram a powered-off spindle into (thankfully soft) wood on a friends machine... No fun.

Also look at the Mesa 7c80 and 7c81 as the Pi plugs directly in to those.
But the Ethernet options are cheaper if you consider that the 7c81 still needs adapting to wire to the stepper drivers.

Do you currently own a PC that you can experiment with? If you do then that would point towards the ethernet solutions. Though personally I prefer the directness of PCI (If I was building a plasma cutter I would consider that direct connection a bad thing, and definitely go ethernet then, for the isolation)

bit off topic but is there any advantage in pci vs spi vs ethernet on the mesa cards?

I feel the spi are is for things that lack the first 2 as they seem to come at a higher price point and more hassle.

Aaroncnc wrote: I feel the spi are is for things that lack the first 2 as they seem to come at a higher price point and more hassle.

Basically, yes.

But functionally they all work very much the same. With the odd exception that I think that the EPP parallel port controlled cards (7i43 for example) actually run at a faster base clock than the others.
However there is no reason to choose one interface over another except for convenience of connecting.

I chose the Ethernet option as I feel, as long as Linuxcnc supports the platform, more or less platform agnostic. And possibly available on a wider range of platforms.
I’m also of the opinion Ethernet ports will be around for a while, barring some laptop type machines. In all fairness I usually wrong more times than right. And a bit of a Luddite, as I miss watching the screamers of the 500cc days, more so than the “easy to ride” Big Bang engines.