I know that changing the firmware for the STM32F103C8 has been discussed before (see here, here and here). But I am still confused.

What I want to do is play around with the ADC of the STM32.

Anyway, I wanted to play around with the firmware and was able to get the open-ec source code compiled. I can upload it with the st-flash tool, but that results in an inoperative system. After using st-flash to re-upload maix_go_cmsisdap_new.hex everything works again. I can also have the compiled open-ec firmware uploaded from platformio using dfu-util. Although it seems that the upload succeeds and the system still works, there seems to be no change. So maybe the open-ec sofware is not what I am looking for?

So, my question is, what software do I need to compile and how do I need to upload it (which tool? which memory location?) to get a fully function system, and be able to play around with the source code to try a couple of things?

@udif, did you do some more experimenting?

@Zepan, in this post you mentioned that the correct firmware is not open source yet, has that situation changed? Is there a way to get source code to compile maix_go_cmsisdap_new.hex?

@Sentry, I have used open-ec because the standard CMSIS firmware did not work reliable for me, while the open-ec version did.
I did not try extending it with more feature.
What are you trying to do with the ADC? I think you would need to modify open-ec for your needs.

I have compiled the open-ec from source, so this would allow me to play around with it. The ADC is not necessary, it is just something to try.

So, the open-ec firmware is all I need? It is not just one component of a number of components? The size is about 9k while maix_go_cmsisdap_new.hex is 93k and flash-zero.bin is 18k. The open-ec firmware seems a bit small.

I have uploaded it using st-flash to location 0x8000000 as well as 0x8002000 (I saw these addresses somewhere) but no working system resulted. When I use dfu via platformio, I have no idea where the firmware is uploaded (I’m not even 100% sure it was uploaded at all) but the system works and there seems to be no change. Should it be uploaded in another way or to another address? Is there a way I can check whether it is working?