I need super basic Help with Hardware choices

andypugh wrote: Is the interface step/dir on GPIO pins, or does it have some higher-level interface to on-hat logic?

Connection-wise? Yeah, it's pretty much that. It connects to the last 16-ish pins of the Pi, that's it. You can run a spindle and coolant, but stepper-wise, it's four connections (Step/Direction/enable/ground) plus endstops. Apart from that, I relly don't know (yet) what the board itself does, i.e. how much work happens on the board vs. on the Pi.

This is the thing:
wiki.protoneer.co.nz/Raspberry_Pi_CNC

I understand now that a Mesa card solution would mean using an FPGA to do time sensitive stuff and I'm assuming with the protoneer board, this will still be handled by the Pi (although I don't know, really), so I guess a Mesa card would allow higher speeds without losing as much precision – is that accurate?

According to what I found, my longest ball screw spindles (1605, 1400mm length) shouldn't go quicker than 6 meters per minute anyway, so that's pretty much the upper speed limit mechanics-wise. Honestly, I have no idea whether that sounds particularly quick.

I'm currently looking into Mesa cards, but am a bit confused, because a) there's so many and b), I don't understand whether just a Mesa card will be enough, or whether I'll need other hardware (apart from a computer, of course) because I see mentions of breakout boards…

In short, I'm almost where I was at the beginning of the thread. I guess I understand better what the different solutions do, but apart from that, I'm still undecided (except that I decided that the parallel port solution won't be interesting for me.).

Twizzlermill wrote: This is the thing:
wiki.protoneer.co.nz/Raspberry_Pi_CNC .

Right. That is running GRBL on the hat. GRBL is roughly equivalent to LinuxCNC and there is no way to use both GRBL and LinuxCNC in a single system (and it makes absolutely no sense to do so).

There are other, simpler, hats that would work with LinuxCNC:
thepihut.com/products/stepper-motor-hat-for-raspberry-pi
For example. That is just a pair of stepper drivers linked to the GPIO ports. However I think it will only run two motors.

You might want to search this forum for "Remora". That might be close to what you want.
Or, the docs here: remora-docs.readthedocs.io/en/latest/

andypugh wrote:

Twizzlermill wrote: This is the thing:
wiki.protoneer.co.nz/Raspberry_Pi_CNC .

Right. That is running GRBL on the hat. GRBL is roughly equivalent to LinuxCNC and there is no way to use both GRBL and LinuxCNC in a single system (and it makes absolutely no sense to do so).

(…)

You might want to search this forum for "Remora". That might be close to what you want.
Or, the docs here: remora-docs.readthedocs.io/en/latest/

Thanks for the answer.

The thing is, I'm really not set either way; I'm not even super set on using as Pi as my computer, but after I fried a laptop at my shop (steelwool… bad stuff.), I'd prefer a Pi because it's cheap to replace. So really, it's not like I'm looking at something specific; I just want my machine to move (and move well) and I'd prefer a Linux-based approach.

A Pi has an ethernet port, so Mesa cards are an option.
But either I'm an idiot or I'm looking in the wrong places (or both), but I have a hard time figuring out what I'd need exactly if I wanted to go the Mesa route. As in, will a Mesa card be enough to get my steppers moving? If yes, which one? if no, what other hardware will I need? Configuration might not be a piece of cake either, but I can get through that with copy-pasting terminal commands (living the Linux pleb life).

I took a look at Remora, but it looks like it's introducing a level of complication that I don't need right now.

the mesa card will not drive a motor directly.
It will make the signal to go to the motor driver and that driver will drive the motor.

Best thing to do is make a list of hardware you have or are going to buy and we can try and help you with what will work or wont.

If you are going to jump the RPi route, be aware that a 2nd corporate desktop may come in at the same price point, only the RPi 4 will work, as all the previous versions have the Ethernet on the USB bus.

Whilst I haven’t looked into costs the RadPad looks like it would make a neat console for a cnc machine. Ok looks like $150 plus the cost of the RPi 4 on top.

Aaroncnc wrote: the mesa card will not drive a motor directly.
It will make the signal to go to the motor driver and that driver will drive the motor.

Best thing to do is make a list of hardware you have or are going to buy and we can try and help you with what will work or wont.

I have drivers; the JMC steppers have drivers mounte to them.
I did mention my hardware in the first post:

What I have/want:

1.: A Raspberry Pi 4 as a computer (with all the other stuff of course).

2.: 4 JMC Closed Loop Stepper motors(Model IHSS60-36-30-21-38); the y-axis will need two.

You did actually mention Mesa cards and that's what made me take a closer look, aor at least made me try to, because I feel like I'm not getting it yet.

I'm not super set on the Pi, but I have one and I thought it's as good as any old computer, so why not give it a go.

And apart from that I'm really wide open for suggestions. Someone mentioned the Mesa 7i76e, would that be a good option? And (apart from drivers) would that be all I need?