SKR Octopus

Hi Everyone

So I have been planning a Low Rider 2 for a very long while (most likely still a while away because I get side tracked a lot, lol ) and I was looking at controller boards and the SKR seems like a good option, though feel free to recommended an alternative.

I was poking around Aliexpress and noticed that a SKR Octopus with 8X 2209’s is cheaper than an SKR Pro 1.2 with 6X 2209s. From a top level view it seems as though the Octopus has more features, Any reason its cheaper / not a good option for a CNC?

Thanks

We have configurations and prebuilt binaries for the skr pro 1.2.

MarlinBuilder releases.

I don’t know much about all the different versions to day beyond that. I will say that 8 is more than you will need for the cnc. 3 is typical. 5 is great. 6 is only for dual endstops with an extruder, which is very rare.

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Yeah I had seen the preconfigured files which is nice but you can always roll your own config right? If there is nothing making the Octopus worse than the SKR Pro I would just download the SKR Pro config and then just transpose those setting (accounting for pin changes) to a new config for the Octopus.

That being said I had not seen the preconfigured files the SKR1.3 and that has the 5 steppers needed and is even cheaper. Any reason the SKR Pro is preferred to that?

Thanks for the reply

The skr pro is an “officially” supported board. Think of it kind of like long term support in linux. I have never run a 1.3 so that firmware is user supported and not tested by me. For the foreseeable future it is not a big deal but when we implemented things like the dual end stops initially it took a while to be supported by any other boards than the ones I/we were testing on.

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If the other board is a bit less expensive now it is probably just an introductory price, they do seem to level out a bit. The Pro bundle bulk pricing just went up significantly (30+%). It took a while for everyone to sell through the on hand inventory, but now the Pro is heading up in price. So saving a few dollars now and having to do your own firmware might not be worth it.

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Yep. You can always roll your own config. That is easier for some than for others. But even for me, I would find it worth some money to not have to do it. You can put your own price on it. There are a lot of helpful people here who would probably help you if you got stuck, but we can only do so much from across the internet.

There are some differences in features on the board. The SKR Pro 1.2 uses an ARM M4 processor, where the 1.4 Turbo uses an ARM M3 processor. There are some additional instructions native to the M4 CPU for some things that we don’t care about, but what we (might) care about is improved floating-point performance. (Do you use G02/G03 commands in your GCode?)

The official BTT site is a mess to navigate to do much meaningful comparison, with the specs listed in different orders, some comparison specs are simply unavailable. The difference for “turbo” seems to be a 120MHz clock, instead of a 100MHz clock, but the Pro (seems to?) out-perform it from what I remember.

As to choosing one to have “official support”, I’d guess that it’s basically that Ryan looked at the options, made an educated guess as to what was going to be around for long to be worth supporting that had a certain desired feature set, picking up that ball and running with it. The SKR Pro supports some really nice drivers, and some economical ones, has a good 32bit processor for “future proofing” and support for the 12864LCD as well as the touchscreen. (Bonus, you can use the touchscreen as a 12864, so good with legacy firmware code.) But that’s the one that he’s configured the firmware for, supports and sells. There’s 1001 different Marlin based control boards out there, it could be a full time job just keeping up with them.

The community support for other boards isn’t bad. It’s actually pretty good, I’ve found, but sometimes you’ve got to wait for “the guy” to respond if you go off the beaten path. Chances are that the latest greatest board out there is usable, but most of us aren’t going to go out and buy one just to configure firmware on it, when we have a perfectly good solution bolted to the side of the machine.

I would assume a SKR 1.3 or similar should suit as far as performance goes . 3D printers move way faster than CNCs and they handle it no issues.

The octopus has the same CPU as the Pro 1.2 from what I can see, just way more outputs .

I might order a Octopus and see how it goes, I rolled my own firmware for my 3D printer and while I think this would have more changes I doubt its an impossible task. If I can get it working we could add that to the unofficial support list and maybe help someone out later. Worst case I take the SKR 1.3 from my 3D printer and use someones else firmware for that and put the Octopus into my 3D printer.

Thanks Everyone.

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hey, i saw the same thing! it is still much cheaper do you order the octopus? if so had to start working on the firmware? in theater there would be what to change with “official” firmware? is that with a documentation of marlin

I ordered one a couple of days ago.

Its currently: Octopus with 8X 2209s was $91 AUD vs SKR Pro 1.2 with 6X 2209 at $107.

As for making your own firmware / config. If normally involves going through 3 config files in a text editor like Atom (roughly pins File, config and config advanced ) and remapping pins / commenting or uncommenting features ect. It takes ages but you can pretty much customise everything as much as you want.

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Any updates on using the Octopus for an LR2? I’m collecting parts for my build and the Octopus 1.1 w/TMC2209’s looks quite attractive - would love to hear if anyone has gotten the Octopus running yet and what their thoughts are. TIA!

Hi I have a working octopus V1 config i edited a fresh copy of marlin 2.0bugfix mine has dual X steppers and dual endstops for Y & Z so may want to edit for that but welcome to a copy if you like :slight_smile:

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it would be great if i could get a copy of your config for my new build

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Hi Kenny I will send a copy tomorrow pal only just seen this

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Thank you ill be waiting on it

Hey lee any luck with config?

firmware.zip (108.7 KB)
Configuration files.zip (87.6 KB)
pins.zip (551.6 KB)
Hi Kenny, Sorry been so long been real busy, can’t fit the full marlin file on here so have put Config_H, Adv_H and Pins File together with a compiled Bin file ready to flash board. My setup has 2 X Steppers and dual endstops on Y and Z axis, single endstop on X axis.
any probs you can get me on here or email me on Lee@advancedhomecare.co.uk

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Thanks ill let you know how it works

Be aware that the Octopus has 3v logic. So the endstops and stepper drivers work on 3v. I personally had to swap my octopus with the Octopus Pro because the Pro has 5v and my external drivers needed 5v.
Also you can get issues wilt voltage drops and noise on longer lines on the endstops, but I am not an electric engineer so not sure if this is a correct.

So, how did it work out? I’ve got an Octopus v1.1 coming soon and thought I’d get a head start while I wait for my other hardware items to be ordered and delivered.
I was going to work from the SKR pro firmware, but I think I’ll work off of Lee’s (considering I too will have dual end stops).