So it could be possible to make a small portable screen device with this, or maybe not because (I think) the RPI is not optimized to work on a battery.

I would prefer a touchscreen with it.

I am not talking about a smartphone, because smartphones are often more powerful, more expensive. I would just prefer a device to do simple computing, with full access to the OS.

Smartphones tend to have android and powerful hardware, and a 4G or 5G antenna. I would just be happy with wifi and enough power to run some C or python code.

I am just curious what is the cheapest screen device that is possible to make with this, as long as it has wifi, a touch screen and be completely open. So far RPI is nice, but it's not really what I want.

▲

javawizard 3 days ago | parent | next [-]

You know the fun thing is, something like the Allwinner A133 - which is one of the most popular SOCs in lower-end tablets today - is like $5, or $3 in quantity.

It turns out it's actually not as hard as you'd expect to whip together your own board with one of those + LPDDR4 RAM + eMMC storage + fixings, and get yourself something like what you're talking about for... I dunno, sub $50? Maybe even sub $20 depending on how much RAM you put on it and what other capabilities you give it.

I'm in the middle of designing just such a board right now. Totally recommend taking a stab at it if you have any EE chops at all (or want to learn!)

▲

fragmede 3 days ago | parent | next [-]

Lets just go with $50 and $20. If you're looking at that on top of the cost of a raspberry pi, comparing that to a super low-end Android phone, used, for something like $80-$100, is that really the way to go? The OS is different but termux has enough features, especially after rooting, that you can probably run whatever you're shooting for. Of course as a hobby, the parts that you find fun don't have to be the parts that I, or anyone else finds fun, so don't take this as me pissing in your cereal, it's more like there's the milk part and the cornflake part and so different strokes for different folks.

▲

whitehexagon 3 days ago | parent | prev [-]

Interesting. I'm currently having great fun learning systems programming on the Allwinner A64, and never considered the option of building a board with one, assuming they are still available. Are you documentating your project somewhere?

	▲	javawizard 3 days ago \| parent [-]
		I'm not but I totally could! Feel free to drop me a line - my email is firstname@website, where both can be found on my GitHub profile (same username as HN). And yes, the A64 is still available! https://www.lcsc.com/product-detail/C3036453.html

▲

wrxd 3 days ago | parent | prev | next [-]

Maybe you’ll find a “cheap yellow display” interesting https://github.com/witnessmenow/ESP32-Cheap-Yellow-Display

It has a display, WiFi, Bluetooth and you can write whatever software you want for it.

It’s based on an ESP32, which is a microcontroller not a full computer like a raspberry pi

	▲	giobox 3 days ago \| parent [-]
		The "Cheap Yellow Display" was one of my favorite discoveries this year, it's now just my default choice for any micro-controller based project with a small display most of the time.

▲

boneitis 3 days ago | parent | prev | next [-]

Funny enough, seeing all types of different suggestions under the sun here in the sibling posts; it's also unsurprising, since I myself can't tell where the gap is between what the Pi offers vs. what you're hoping for, as that would have been the first thing I suggested.

In addition to all the other suggestions, you might look at PINE64's offerings. Maybe one of their tablets, their PinePhone, or one of their SBCs or SOCs.

▲

pySSK 3 days ago | parent | prev | next [-]

If you’re looking at something with a screen, the ESP32 ecosystem has tons of options. Look up Waveshare and Elegoo ESP32 modules.

▲

AnthonBerg 2 days ago | parent | prev | next [-]

Some of the gaming handhelds that have mainline Linux support might be the ticket.

Ah, and the Vivid Unit: https://www.vividunit.com/Main_Page

▲

adhamsalama 3 days ago | parent | prev [-]

You buy any cheap Android phone and run Termux on it.