ESP8266 Community Forum

Don't worry about the names of the flash files - it's more important to make sure
- genappbin and esptool are fed the correct flash size
- esptool is fed the correct locations to flash

All your esptool command lines are for different flash sizes. Go into the makefile I sent and look through it till you find the settings for flash option 6. These will give you the right numbers to use in your script

Also can you zip up your entire project and attach here? I will reformat it to use the makefile I posted

Davey, I got FOTA to work after flashing to the correct location. It only took 8 months of forum support on this shitty nondocumentation feature. The document by Espressif says to refer to the MakeFiles in their sample projects is a huge pain but after fiddling around with it I only needed to use Elf2Image in the latest ESP tool to generate the correct userbin files.
Davey I really appreciate your attempt at assisting.
I'm wondering, What does the GenAppBin do? Is it supposed to modify the LD files on the fly to match the size of the SPI on the given ESP chip?

No the genappbin app is actually a Python script (you can find it and read it in the SDK tools dir) that takes the compiled and linked image and turns it into the correct memory map format for the flash tool, writing the flash header data for the size, speed, boot mode, start entry point, etc. as well as CRCs for the file

Where do I find this Makefile (somewhere here on the board?) - I am also looking for a Makefile that builds the two bins...

Any hint welcome!