I thought I’d just share a quick idea with you all. Framework said a while back that a display input module would be really hard to make due to the height restriction of 3.7mm.
It might however be possible to cram a 7-segment display in there, for example to display CPU, GPU and RAM stats. Moreover, this would probably lead to less power consumption than an LCD display.
Does anyone have an idea if this is possible or viable to make? I myself am unable to make these since I have very little technical knowledge. Maybe someone else wants to make this. Thanks in advance for the ideas!
Considering how expensive the replica apollo displays were to make you’d probably be coming out cheaper using a smartwatch oled or something for each digit or something.
You might have to do something weird where you have holes in the module PCB that these then fill and then get held by the soldier instead of being placed on top of the module PCB.
They are designed for surface mount, so there would be no holes in the PCB unless vias are needed to feed the signals through to a different track layer.
However another possibility could be to make a hole large enough for the body of the display and have the display mounted on the back. This would also help if using the VDMR10A0 displays which are about another 1mm thicker - but also come in 4 colours instead of 2. I twigged to the A0 version by following the ‘you may also like …’ links at the bottom of the link in Jacobs post.
I apologize for my lack of clarity. I did mean something like what you suggest as a possibility in the second paragraph. But you suggest mounting the top face of the digits’ PCBs to the back of the module’s PCB whereas I suggested attaching the edge of the digits’ PCB to the inside of holes cut into the module’s PCB.
As much as I like that black solder mask, I think I’m going to make one tweak before I sent this off to JLCPCB – instead of printing the logos on the board itself, I’m going to add a few white LEDs, and I’ll 3d print a frame to tidy everything up with an opening for the legends, and then cover the entire front face with a sheet of grey mylar. Then you’d be able to swap out whatever legends you like by making an appropriate transparency and have the legends be backlit.
It uses more or less the same LED driver chip as the Framework LED module does, so in theory should be able to use the same firmware as well. Maybe a tweak or two is needed, I can take care of that.
Of course you’d want to hook it up to actually display CPU/GPU/RAM usage, and that part I’ll probably leave up to others.
Here’s the PCB and bezel design for a seven segment display input module which I’m sending out to have fabbed by JLCPCB;
The idea is to print out your desired legends for the three displays on 4mil transparency, and then cover the entire thing with a 0.2mm ND filter for a clean look. The electrical design is very similar to the framework LED matrix, so very similar firmware/driver should work.
Haven’t tested the NeoPixel LED support because I don’t have the hardware, so there might be tweaks still to come. This was my first time programming an embedded system in Rust and I’m not sure if I love it or hate it.
I wasn’t happy with how the backlighting of the display legends turned out, so that’s off in this photo, and I think I want a matte tint film not the glossy one in this photo.
Probably going to switch from sidelighting of the legend to some sort of more direct backlight, maybe with a secondary PCB to serve as the shadowmask. Won’t be quite as easy to swap out the legends but I think it will look better.
Also if you like this please comment rather than just like, as the forum software won’t let me continue to post updates unless other folks reply in between my posts.
Testing out a new method of making/backlighting the legend. Its better than before, but I’m not completely happy with the unevenness. I’ll try something else, probably switching to smaller neopixels that less tall so the light has a little more room to spread. I think the small legends need two LEDs, not just one, and the larger legend needs two LEDs for the capital letter and letter with descender. Sigh.
