A while back i wrote with somebody that still used a Z80 for his diary. I actually find the idea quite charming since knowing your running code is actually feasible. Has anyone here a similar setup? While that hardware was before my time there really shouldnt be any major hurdle in using something the size of a Cortex M (no secure co-processor!) despite its lack of a MMU. They also come with AES acceleration usable for file encryption, enough USB for a keyboard as well as SD-Card reader and LCD via SPI.

Details:

To give you an idea what is possible, here somebody put ucLinux on a beefed up(more memory) Cortex m3/4

https://www.electronicdesign.com/technologies/embedded-revolution/article/21795660/practical-advice-on-running-uclinux-on-cortexm3m4

>The interactive shell is fast; response times are on par with those of Linux on a PC. No sluggish-ness; for instance, things such as a vi session on a local or NFS-mounted file can be run quite comfortably.

Get rid of linux and you should be able to use stock SOCs

I especially got curious because thats the size of the hardware of not just ikea light bulbs but smartwatches like the pinetime. Which already got RIOT OS support with lvgl for the GUI.

And LVGL can make quite nice guis for its footprint. https://lvgl.io/demos And they got keyboard support.

As i see it, the only real hurdle is getting a real text editor running with lvgl. The current implementation is ofcourse not geared towards longer texts and there arent really any text editors for such devices(that i could find). Getting org-mode running is rather infeasible but there are things like vi for busybox which can get quite small.

Sooo long story short, who of you is already doing this?