Coding Custom ESC Firmware From Scratch in C language

Ok so after further consideration I decided that the idea of adding significant modifications to a 6k lines of code 20 file assembly language behemoth firmware developed by a big company was just not prudent for me. I need to be able to go in there and add tweaks and improvements for years to come and maintain my code there. The firmware of the ESC is absolutely essential to get just right as it has a massive impact on the performance of the final humanoid robot. The speed and fluidity of movement, the amount of strength, the amount of acceleration, it is all impacted by this. This is just essential. And assembly language is not in my wheelhouse. I am very inexperienced with it. So I officially decided to simply scrap their entire firmware and start from scratch coding firmware for it in C language. I have begun that process and so far so good. I will say though that the Keil PK51 Developer's Kit is an evaluation version and is necessary to convert the C code into the .hex file the microcontroller needs. The evaluation version limits your code size to 2kb which is unacceptable. To get the full version and get that restriction unlocked you have to fill out a form on their website (silabs.com) and they send you a code by email and you can then use that to unlock the software fully. So I did that and am now good to go on that front. While beginning this long journey, I also have been figuring out how single wire bi-directional communication between my arduino "flight controller" and the 8051 Busy Bee microcontroller on the ESC will be able to talk back and forth. I decided to make a custom communication protocol from the ground up for this which I will also then use for all communications between all of my various microcontrollers in my robot's microcontroller network throughout its body. So working out the details of that has also been a recent challenge. But with chatgpt's help I'm making steady progress and have a nice overall plan already. Things are moving along nicely.