Duet 3 Mainboard 6HC - initial production run.

[JoergS5]

@leonmf so maybe it's better to setup the operating system as read-only, similar to http://hallard.me/raspberry-pi-read-only/
and held the non volatile data in a separate storage.

[T3P3Tony]

Good points. One way to go is to have the power configured so the Raspi does not shut down, or at least is in charge of the shutdown. So power off just sets the printer into a low power sleep mode where the 24V is off and only a little 5V is used to keep the Pi idling... When you turn a modern TV or whatever that is what happens...

[dc42]

@knaudler said in Duet 3 Mainboard 6HC - initial production run.:

screws for Power ?
something like this would be nice:
https://www.wago.com/de/leiterplattenanschluss/klemmenleiste-fuer-leiterplatten/p/2716-102

I've taken a look at the Wago range of push-in connectors. Many of them are either too large or very expensive. The most suitable 6-way one I found was this one https://uk.farnell.com/wago/2092-1376/terminal-block-wire-to-brd-6pos/dp/2352417. Like most push-in terminals blocks, it's only suitable for use with solid core wire or stranded wire that has been terminated with ferrules already. So if you need to use stranded core wire, it doesn't avoid the need for crimping, and it's hard to justify the additional cost.

For the home user, an advantage of the barrier strips we currently use is that crimping tools for automotive-style fork receptacles are very cheap. But I can see that some OEMs might prefer push-in terminals to speed up wiring.

[A Former User]

Back in the day, we ended up with a compromise and used pluggable terminals where phoenix contacts had both screw and push-in female connectors, the boards used the same male header (but that was only up to about 10A iirc)

Also found that you could use stranded wire without ferrules, but then you loose the tool-less advantage as you need to press the release spring to insert the stranded wire. And something like Radox 125 is wound so tight it can be inserted without ferrules in a pinch, but for production you'll want ferrules anyways.

But yes, quite significant savings on wiring time with push-in terminals when wiring is prepared by machines automatically cutting, stripping, labeling and crimping ferrules. However unless you have the machines I doubt its worth the investment for a single 6-pin terminal.

[JoergS5]

@leonmf I bought a Pi 3+, but will buy a Pi 4 also, because he has a lot more I2C and SPI interfaces (about 5 each, 3 + has only one useable SPI, which will be used to communicate to Duet), so if one wants to use Pi4 for additional tasks like using cameras (e.g. Arducam with SPI/I2C interface), additional I2C and SPI are useful.

[KP0005]

Regarding the SPI connection, would it in theory be possible to connect a Maestro to the SBC in a similar way?

[dc42]

@matej101 said in Duet 3 Mainboard 6HC - initial production run.:

Regarding the SPI connection, would it in theory be possible to connect a Maestro to the SBC in a similar way?

In theory yes, with a lot of firmware changes. Ideally the W5500 Ethernet chip would be removed to free up the fast SPI connection. I guess the daughter board SPI could be used instead, at a lower speed and by dropping support for external SD card sockets and temperature daughter boards.

[KP0005]

@dc42 thank you for the quick reply! I'm not really experienced with programming so redoing part of the firmware seems to be a bit of a stretch for my use case. Guess I'll just hack something together instead.

[A Former User]

@matej101 said in Duet 3 Mainboard 6HC - initial production run.:

@dc42 thank you for the quick reply! I'm not really experienced with programming so redoing part of the firmware seems to be a bit of a stretch for my use case. Guess I'll just hack something together instead.

No hacking needed just buy a Duet 3..............

[KP0005]

@calvinx but money...

[mundsen]

Order one today, plan to use it in my Corexy project 🥰

[dc42]

@matej101 said in Duet 3 Mainboard 6HC - initial production run.:

@calvinx but money...

It's occurred to me that a Duet Ethernet without the Ethernet daughter board should be relatively straightforward to connect to a RPi. Maybe I'll add support for this in the future.

[gtj0]

@dc42 said in Duet 3 Mainboard 6HC - initial production run.:

It's occurred to me that a Duet Ethernet without the Ethernet daughter board should be relatively straightforward to connect to a RPi. Maybe I'll add support for this in the future.

That could be VERY handy!

[denke]

@dc42
As I remember the wifi can also be converted to ethernet. So, Is it possible for that too?

[dc42]

@denke said in Duet 3 Mainboard 6HC - initial production run.:

@dc42
As I remember the wifi can also be converted to ethernet. So, Is it possible for that too?

Yes, if you removed the WiFi module.

[dc42]

The tests on the first Duet 3 main board have passed over the weekend, so assembly of the first batch is now under way.

[Veti]

@dc42
congratulations. nice to be able to follow the development cycle as is progresses to the final product.

[mundsen]

I have order a Duet 3 - is it possible to get a 3D model? I`m designing my own railcore based corexy printer - hope to spend the time while waiting for the controller to arrive designing a housing for Duet + PI

[A Former User]

@mundsen

the pcb size and major component location is already available on the duet website. that's what I used to allow me to design a suitable holder

[dc42]

@calvinx said in Duet 3 Mainboard 6HC - initial production run.:

@mundsen

the pcb size and major component location is already available on the duet website. that's what I used to allow me to design a suitable holder

https://duet3d.dozuki.com/c/Duet_3_Hardware if you can't find it. The details of the 3HC expansion board are for prototype 2 but we don't intend to change the dimensions for the production version.

We also have another Duet 3 family board about to be prototyped, but we're not releasing details yet.