ENGAGE VS embox

Could be, take a look at the batteryless Gameboy for example: https://github.com/TUDSSL/ENGAGE

But I don't know how to design at all, and RAM on its own is a lot harder to integrate into a board, and isn't as simple as soldering 8MB PSRAM on a Teensy pad. That said, this academic group did that with An Apollo3 MCU: https://github.com/tudssl/engage The Apollo4 will have 1.8MB SRAM, which I think will be more than a lot of these boards have https://ambiq.com/apollo4/ at much lower power. The Apollo3 Blue+ has 768K SRAM.

Thanks for the analysis! I am not an engineer so I try to glean as much as I can from this so hopefully I can find the right components and discard the things that aren't needed. This board here used the same MCU in my link above: https://github.com/tudssl/engage so I am looking for ways to turn it into a solarpowered laptop with e-ink that doesn't shutoff/sleep every 10 seconds but can idle 24hrs using a few of these https://www.powerfilmsolar.com/products/electronic-component-solar-panels/indoor-light-series/ll200-2-4-75. I had considered the ESP-32WROVER with 8MB RAM but the PSRAM is not as low power as FRAM.

I became curious because this project ran a game on a 48mhz processor using FRAM: https://github.com/tudssl/engage

Embox is a configurable RTOS designed for resource constrained and embedded systems. Embox main idea is using Linux software without Linux. (https://embox.github.io/ ) If you want use complex Linux Software and Linux is huge for your goals. Embox is the best idea, as I think. For example Embox is the only RTOS that allows to use OpenCV on Cortex-m MCUs https://www.embedded.com/benchmarking-opencv-on-stm32-mcus/

Look at Embox (https://github.com/embox/embox). It can run on EFM32ZG with 32kB ROM 4kB RAM

Take a look at Embox - https://github.com/embox/embox

As for Linux, it allows easy and fast creating a device with reach features, but it requires more powerful and expensive hardware platforms, it has some questions with hard real-time, and it is less secure after all it is a general-purpose OS. We try to solve these cons of Linux in Embox. It combines prop RTOSes and Linux and allows run Linux software everywhere including MCUs

We try to solve these Linux disadvantages in our way in Embox project. The project allows run Linux software everywhere including MCUs.