Over the weekend I found a bug in the checksum calculation in esptool2. It caused some images to have a bad checksum, which would then not be bootable as rBoot would think they were corrupt.
If you haven’t already please pull the latest source and rebuild it. Or if you are on windows and using an old pre-compiled copy you can get an updated version here.
Time to write something about esptool2, as I’ve been using it in the last few posts. The SDK way of creating rom images is a mess involving a shell script / batch file and Makefile. I did find a windows version of esptool by mamalala, but it didn’t create the newer rom format used by the SDK boot loader. So I wrote my own. I used a simpler design and command line compared to the version by mamalala (which I think is designed to be a drop in replacement with compatible command line interface). Although I prefer it this way I didn’t call it esptool2 to imply it was better or a replacement and I hadn’t originally intended to release it.
Features
It doesn’t flash though, so you’ll need something else to do that, sorry. Never done any serial programming in C and I suspect it’s probably difficult to do in a nice platform independent way. If you can do this please get in touch.
Get the source from github: https://github.com/raburton/esptool2 Or get the compiled version for windows: https://www.dropbox.com/s/03ci9orf9ccr9ya/esptool2.exe?dl=0
Run it to see full usage instructions or look at the rBoot sample project for usage examples.