esp32-elfloader VS libnklabs

The process generally the same for 32-bit binaries. If you want more specifics, this is fairly basic and 32 bit.

..and what should this say about esp32? I don't understand what you are implying...

xtensa/tensilica is a good architecture, cheap and lean, unfortunately its biggest problem seems to be its harvard architecture and weird memory structure because out there I find very few loader/relocator impementations (nominally I only know niicoooo's version[1], brian pug's derivative[2] for his interesting joltos, mongoose/Zephyr's supercustom versions, and my own) and this seems to be the main stumbling block for new os development in this platform

[1] https://github.com/niicoooo/esp32-elfloader

[2] https://github.com/joltwallet/jolt_wallet/tree/master/jolt_o...

Two issues with readline: it's GPL and it's big. For embedded systems intended to become products you really need something else. My tiny variant is this, but for sure there are many others:

https://github.com/nklabs/libnklabs

("nkreadline" has editing, tab-completion (for embedded "nkcli" commands) and history)

I used RTEMS on Movius Myriad vision CPU (running on LEON- a SPARC clone).

I remember the RTEMS event concept was not very good- the events are globally shared. You are better off using semaphores.

>I have realized that for a majority of the embedded software using an RTOS is an overkill

I agree with this. Instead of an OS, we like to use a small framework that provides a CLI, database and UART communications (YMODEM protocol). It's a single stack system that provides a simple work-queue for scheduling future tasks / callbacks, and for interrupt code to schedule non-interrupt code. It works for almost everything as long as you are comfortable programming in an event-driven style.

https://github.com/nklabs/libnklabs

(recently added support for AVR 8-bit processors).

I've extracted the Chromium-EC encryption functions, they are convenient for signing / verifying firmware on other platforms. Chromium-ec is nice for example code like this:

https://github.com/jhallen/rsa-verify

On the other hand, if you are looking for some generic embedded system code all in C, here is our library:

https://github.com/nklabs/libnklabs

I think it's most unique feature is the embedded schema-based database- so you can save things like calibration and configuration information in local flash memory. Recently I've been adding device drivers for all common devices I can find on break-out boards for the Arduino and Raspberry-PI communities.