Connect Pi 4 directly to Einsy like the Pi Zero
I want to connect a Pi 4 to the Einsy. I plan on connecting through the front of the board; it looks like I can go through the front or the back.
Who out there has done this? What is the pin configuration I need? Do I need a separate power-supply, or can the Einsy power it? I'm hopping someone in the know can help me before I kill my printer and a Pi.
Thanks
RE: Connect Pi 4 directly to Einsy like the Pi Zero
Pi4 can't be powered directly from Einsy. Either use a separate PSU or get a DC-DC converter. You need at least 3Amps@5Volt.
In regards to connection type, is there any specific reason to connect it via Serial port instead of USB?
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RE: Connect Pi 4 directly to Einsy like the Pi Zero
I have connected the Pi3B directly to the Einsy via the connector on the board. Supply is via DC/DC converter connected to 24V on Pin 1 on the Einsy header. Check the Einsy schematics for details (header J19). There is also an example on Thingiverse: https://www.thingiverse.com/thing:3289419 But do not connect the 5V pin to the Pi4!
It works great, you have only one cable between the Pi-box and the Einsy and the USB port is free for firmware updates. You can connect the header on the Einsy from both sides, that's correct.
I prefer this solution to the connection via USB. Yes you have to solder a cable and you have to be careful, don't make a short circuit between a signal pin and 24V. But if you know what you are doing you have a rock solid 'industrial type' connection not making any trouble. At the end connecting via USB port or the Einsy header are working both. It's more a question of personal taste.
RE: Connect Pi 4 directly to Einsy like the Pi Zero
@nikolai-r
I had heard that connecting directly allows for a faster connection resulting in less printing errors. Was I misled?
RE: Connect Pi 4 directly to Einsy like the Pi Zero
Interesting. I had heard that the USB interface, implemented and buffered in hardware, led to less printing errors. Less under-runs and over-runs.
Who is going to run a definitive test for us?
RE: Connect Pi 4 directly to Einsy like the Pi Zero
@mtnmage
Most likely, yes. The speed should be the same at 115200 baud rate. USB to serial connection is less error prone because all cables are shielded properly. If you're making your own serial cable, you have to make sure it's shielded and if it's too long also have ferrite core around the wires.
Will say this shouldn't be a reason to go this route.
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
RE: Connect Pi 4 directly to Einsy like the Pi Zero
@robert-rmm200
As far as I remember Octoprint is adding line numbers for each gcode line. over-runs and under-runs shouldn't be an issue anymore. But this would be a question in the Octoprint forum. Haven't look into the implementation there.
Regular Raspi/Linux is not a real-time system. USB bus and the kernel can be always overloaded depending on your setup. If you hooked up many devices to your USB then you might have issues with fast prints through USB. On the other hand if your system have a high IO load and depending on the serial kernel module used for the direct serial connection you might have more issues with this connection type. Means depends on scenario the one option is better then the other.
Anyway, most common reason to go for direct serial is usually to keep USB port on the board unoccupied. In regards to connection stability I would rather go with regular USB connection.
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
RE: Connect Pi 4 directly to Einsy like the Pi Zero
Main reason I went USB is I do not want to accidentally fry my Einsy board. Those GPIO pins are an accident waiting to happen if you are not careful.
RE: Connect Pi 4 directly to Einsy like the Pi Zero
Thank you all for the insight. It sounds as though there is not a real benefit to attaching it all directly, unless I just want an all-in-one setup. That doesn't matter to me. I'm just always looking for ways of improving my setup.
I'll probably leave it alone for simplicity sake. Back to trying to solve that stupid Y-crash issue now...
RE: Connect Pi 4 directly to Einsy like the Pi Zero
Thank you all for the insight. It sounds as though there is not a real benefit to attaching it all directly, unless I just want an all-in-one setup. That doesn't matter to me. I'm just always looking for ways of improving my setup.
I'll probably leave it alone for simplicity sake. Back to trying to solve that stupid Y-crash issue now...
RE: Connect Pi 4 directly to Einsy like the Pi Zero
I did this with my 3A so I could keep the single USB port open. Powered separately so I basically connected all the pins as specified for the pi zero, except the 5V. I connected it on the opposite side from where the rpi zero connects so the wires are not sticking out. Never had any issues.