Wireless firmware upload for uECG!

A project log for uECG - a very small wearable ECG

It's cheap, doesn't use a specialized heart rate AFE and can blink LEDs with your pulse :)

Ultimate RoboticsUltimate Robotics 10/03/2020 at 13:120 Comments

You probably have noticed that updates began to appear more and more often!  To be honest, we are also happy about this...

The development of the device partly coincides with our development, too, because the technologies we apply here are related to our growth as specialists. For example, a year ago we were able to make only primitive applications - rather, more data output to the screen - and over the past six months the quality and functionality of the application has grown significantly.  

But today I would like to tell you a little about the technology that we have been trying to implement over the past few years: the bootloader. It is very strange, but no matter how we looked, we hadn't seen a single post covering the whole process, a single implementation available. Possibly it is because Nordic's softdevice has it, and even though this code is closed and proprietary, it gets the job done - so people are more or less ok with it.

Not us though. And it's in fact a very simple thing - but somehow it is not properly described anywhere! So we had to improve our knowledge of ARM architecture, linker scripts, physical memory layout of the program - and when it was good enough, actual programming of a wireless bootloader took less than two weeks. Yet the whole way to that point took about 2 years, with 5 or 6 failed attempts in the process. Hopefully our code and notes would save this time for anyone trying to do the same:

So, at the end of August it finally became possible to upload firmware via radio! It is very cool! And we hope reliable... so we advise you not to rush to throw out st-link programmers just yet... We filmed a video review of the firmware upload process and will add this part to the instructions. But we will also record a separate video so that everyone who received the device before September 1 can upload the firmware without a programmer.  

So we'll be in touch! And write if you have questions / suggestions / and just kind words!