Have you ever spotted something in a catalog or on a website and just known you had to build a project around that one part? That’s how [nilseuropa] felt about the Waveshare ESP32-S3-RLCD-4.2, which — as you might guess from the name — pairs an ESP32-S3 with a reflective LCD. With a screen reminiscent of a palmtop of yore, [nilseuropa] wanted a personal device, and needed something to run on it. That’s where Solar OS comes in.
Physically he’s paired the Waveshare board with a mini keyboard and put them together in a handsome 3D printed case with a battery. The slabtop form-factor was more for ease-of-creation than any preference; in the project’s reddit thread [nils] is reaching out for help making something cooler, possibly of the palmtop form-factor. He also describes some of the thinking behind his operating system.
He’s not starting entirely from scratch: it’s based on FreeRTOS and the ESP-IDE toolset. Right now all applications are built with the OS into a single binary, while the SD card on the Waveshare board handles persistent storage. The interface is pure text, with all applications launched via shell commands. That doesn’t mean you have to go back to your PC to add anything, however.
The system is user-programmable, with Python and Lua scripting as “first class citizens”, having access to the hardware through the Solar OS APIs. As for the applications built into the firmware, it looks like along with the serial terminal, you get quite a lot: an orthodox file manager à la Norton Commander, networking tools that include a web browser and chat client, MP3 player, image viewer, text editor, games, and more.
While they are obviously pretty niche projects, we do appreciate that there’s a growing collection of homebrew operating systems that you can run on your bespoke computing device.
I think i may be possible to add a PV element layer to the bottom layer of an LCD and get solar charging from the display from ambient light.
Just a thought i had looking at a glass PV element from a garden lamp….
I bought a version of this reflective LCD but with an easier connector, and it is slightly translucent.
There are solar watches that put their solar panel underneath a mother of pearl dial, so why can’t we do the same thing and get an ultra-efficient harvesting circuit?
My thoughts precisely…
If you think about that stack in a LCD panel the bottom layer is mostly made from Mylar mirrors.
Most people that want this sort of device would be impressed if part of the process involved adding the PV glass in lieu of the common reflective layer… than as it’s powered off it can recover even large cells over time just being in light.
The Display is a large part of all systems like this, It would be trick to figure out a thin layer PV to insert into a common display and add that option.
If enough hackers start doing it, China will add the function to commercially sold parts soon enough.
It just seems like lost real estate a crafty person can capitalize on adding solar recharge to the already watt sipping ESP32 setup.
Perhaps a multi battery setup if the device is outside a lot…
It really made the wheels spin as i read the story….
A PV panel almost by definition is dark: By design it absorbs light.
Reflective LCDs are fighting for every bit of contrast and visibility they can deliver. Making the background darker by turning it into a PV substrate won’t be helping matters.
You’ve got just as much black surface area in all the surrounding areas: Make THAT PV area.
Look at a solar cell on a calculator…
Put that just above the mirror layer on the bottom.
In full light it will give enough wattage to run the whole thing and even offer a bit of charge to the battery.
Not all solar cells are dark.
haha man i want to tell you about the negativity in my soul, and perhaps not say anything meaningful about this project at all.
i see a project like this — just the headline and photo — and i immediately have two thoughts: this will never be used, and it shouldn’t use the raspberry pi. and what i’m sad about is that just recently, in the past few months, i have come to always think a third thought, even more negative than the first two: the software is the lowest grade of slop and offers a stochastic dream-like vision of what it is to use a computer.
so i looked in this project for a mirror of my black soul, and i still think it will never be used. but i was wrong — and gladly so! — about raspbery pi. it’s esp32, imo a perfectly suitable processor for such a device. and honestly the software development is absolutely inscrutable to me. compared to the lowest grade of slop, it seems to incorporate a lot of open source projects, which is a great way to add a ton of features in short order. but all of the commits are massive mega-commits with multiple huge steps in one commit…so i really can’t imagine, how was this process performed? did someone ask chatgpt to incorporate open source projects? like, if the timestamps in the commits mean anything, then this was done by someone who is extremely efficient at the task of porting open source projects to a new platform, one way or the other.
so i guess i’m left with questions about how dark the world is, compared to my soul, haha. it’s sure eerie to see people doing things i always dreamed of doing, but the scale of the accomplishment is unclear now.
You ok?
you tell me, man
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