Can anyone point me to the product data sheets (how to program) both the 7.3” and 13” Spectra6 displays? I would like to program the displays with go instead of Python (go runs super nice on Raspberry Pi 2 W with Raspberry Pi OS 64bit Lite). Rather than just converting the Python code (which is a fallback option) I’d like to learn more about the Spectra6 displays.
I asked the same question directly to Pimoroni support. They can’t provide a datasheet. Given the fact that you cannot find it anywhere (I didn’t either) you are left to reverse engineering the Python code. Which is not a dramatic exercise. I did it to port the code to CircuitPython.
You program the device by sending a sequence of bytes to the chip. You basically have to implement four things:
init sequence
write sequence (this degenerates to a b’\x10’, which is fairly standard)
Still, I am curious to find the documentation. I am also curious why it is kept as a “secret” by the manufacturer of the panel. When you are writing “can’t provide a datasheet” I guess you are saying “bound not to disclose it by some form of legal contract”?
There’s a lot of “secret squirrel” in the electronics industry, with people having to sign up for things to get access to datasheets, maybe even things like confidentiality and non-disclosure agreements.
If you ever followed discussions around Raspberry Pi, there was often considerable tension between members of the community and the makers of that product around access to documentation. Usually, the “reasons” given when people ask for documentation on such projects/products is that (1) they don’t need it, (2) someone already wrote the driver code, (3) it is “commercially sensitive” information.
In some cases, the manufacturers are probably afraid of being sued for patent infringement by their competitors, and so they make these documents inaccessible and make people sign agreements that prevent them from sharing any technical information. Amusingly, even companies that openly publish their datasheets and programming manuals may leave the “confidential” watermark in place.
Pimoroni wasn’t very specific about that. As a side note: Waveshare has similar displays and they usually publish all the datasheets for their products. But not for Spectra6. So this is probably driven by the manufacturer.