can a lime 2 or pico 2 xxl run an open printer in a free software manner?

[oeren]

https://www.crowdsupply.com/open-tools/open-printer

In the following I am assuming that the software which is running the open printer is free software.
Unfortunately the open printer people decided to go with a rpi zero w. The rpi zero w requires non free software in order to work. In result free software people do not want to use the open printer. On the other hand should it be possible to replace the rpi zero w with a computer able to run entirely on free software the open printer would get relevant for free software people.
Both lime 2 and pico 2 xxl can run entirely on free software correct? If so can I get to know if the lime 2 and pico 2 xxl are candidates for replacing a rpi zero w?
Please do not provide answers if you are not familiar with what free software is in the context of the free software foundation. Thank you.


 

[LubOlimex]

All three of the boards that you mentioned can run completely open source software. Yet there is major difference between the Raspberry Pi product and Olimex products - Raspberry Pi Zero W is not open-hardware, while Olimex provides files used to manufacture their products, when it comes to A20-OLinuXino-LIME2 and PICO2-XXL. These are open-hardware products.

About the software - the official Linux image provided by Olimex for A20-OLinuXino-LIME2 is truly open-source software, and contains no binary blobs. This is mentioned in the Olimage guide here:

https://github.com/OLIMEX/OLINUXINO/blob/master/DOCUMENTS/OLIMAGE/Olimage-guide.pdf

PICO2-XXL doesn't come with own software, the software Olimex provides for PICO2-XXL is based on the RPi SDK, so expect similar software as what Raspberry Pi Zero W uses.

[Roman]

The rpi zero w requires non free software in order to work.

Quoting from a Stack Exchange answer for context.

The Pi Zero uses the BCM2835 system-on-a-chip, which combines a CPU and a VideoCore 4 GPU ... the GPU bootstraps the CPU and loads a kernel into it ... the firmware required for the GPU is from closed source.

In contrast, A20-OLinuXino-LIME2 does not require any proprietary binary blobs to boot. For example, Guix System, which is compliant with the Free System Distribution Guidelines (FSDG), is known to run on it.

However, A20-OLinuXino-LIME2 is much larger, it is twice as wide as Raspberry Pi Zero W. Would it be possible for Open Printer to fit it in their design?

PICO2-XXL is a "re-design of the popular 'Raspberry Pi Pico 2'", so it does not run GNU/Linux. Could Open Printer still use it?

[oeren]

All three of the boards that you mentioned can run completely open source software.

When you say all 3 of the boards and by that include the rpi zero w, you are wrong. The rpi zero w requires non free software in order to work.

In fact no rpi computer is able to run entirely on free software. According to a rpi engineer the raspberry pi pico 2 requires no non free software in order to work.

[oeren]

Quoting from ...

all rpi computers are a nuisance in terms of free software. Because no rpi computer will work even partly if you do not give them the non free software they require to run.

possible for Open Printer to fit it in their design?

Free software people take what they can get. If a free software computer can replace the rpi zero w then it does not matter if the computer has to be put somewhere outside of the printer.

does not run GNU/Linux.

I had not put any thoughts into that. I am not a programmer. Therefore my investigations are the investigations of a layperson. And in any case they can be wrong.
I have been told, it is common that printers and 3d printers are run by micro controllers. Suggesting a pico 2 xxl should be able to run an open printer in terms of performance.
On https://www.opentools.studio/ it says open printer will make use of open source print server CUPS. I guess open printer is referring to https://github.com/openprinting/cups
I cannot tell if the cups software can be put on a pico 2 xxl as is. Or should rewriting the cups software be an option for getting the software on a pico 2 xxl, how big a task that would be?
Should a lot of consumers be interested in buying an open printer running entirely on free software the open printer would present a business opportunity for olimex. I think olimex should contact opentools.studio in order to find out if an open printer version running entirely on free software can be made?

[Roman]

I couldn't find a specification, but, looking at their marketing materials, it appears that the Open Printer project implements the control module as a HAT on top of a Raspberry Pi Zero W and tailors the shape of the control module to accommodate the board of that particular size. Assuming that it is the case, it sets constraints on what the board must be. I doubt that Open Printer will want to adapt their design, even in a future iteration of their printer, to accommodate the shape of one of Olimex boards, which are comparably less widespread.

Olimex doesn't sell a drop-in replacement for Raspberry Pi Zero. Olimex boards are typically larger with more interfaces and are not pin-compatible with that board. Also, the market is already crowded with Raspberry Pi Zero clones, so I assume that it is hard to justify developing yet another one.

Unfortunately, all the ARM-based clones of the board that I am aware of require some binary blobs to boot.

However, there is an existing product on the market from another manufacturer that you may consider. There is a pin-compatible board in the same form factor as Raspberry Pi Zero, which is known to boot without proprietary blobs in uboot and in the Linux kernel, and on which it should be possible to run CUPS. There are several caveats to keep in mind. It is based on Allwinner D1, and thus, is RISC-V, not ARM. Also, I could only find versions with built-in Wi-Fi, which is not expected to work without a blob. But the onboard WiFi module could be kept uninitialized, or, alternatively, desoldered completely. So, it can be used entirely with free software. And it should be possible to adapt it for use in Open Printer.

Speaking of Wi-Fi. Open Printer only lists two options to connect the printer: either over USB Type-C directly to a computer or over Wi-Fi. They left Ethernet out, so one will have to write a USB driver for the board and connect the printer to another computer. That another computer could be an Olimex board, but it does not require any customization by Olimex to work.

Considering the above, it probably makes little sense for Olimex to get interested in Open Printer at this point.