@tekka pleeeease.... :pray:

@JamesT42
Hi, it is hardcoded within the bootloader: nRF24 (Channel 76, base address 0xA8A8E1FC00, data rate 250kbs)

@Anduril

1. I agree, keys located in sketch can be used as workaround only, because the security is broken.
2. But I'm interesting in key located in EEPROM. How it is work during flashing? If Clear EEPROM fuse is not set then everybody can take my outside node, put his own firmware and it will work with keys from EEPROM. It is again a security issue (of course he must have physical access to my node).
   I thing it should work with this scenario:

• reguest for new firmware
• copy key, serial and rsa into RAM
• flash new firmware (with fuse clear EEPROM)
• copy key, serial and rsa back into EEPROM

What do you thing?

@NiklasO I'm using Arduino Mini 5V, 16Mhz with fuses as you have. Except BODLEVEL 2.7V and EEPROM Cleared. OTA works fine, 21kB hex file is sent in cca 2-5 minutes (very depends on count of wrong packets, without 47uF capacitor on NRF24 or with low power supply it takes about 2 hours :) ). I started with MYSController and small and easy Blink.ino.hex from MYSController distribution. Now I use MyController and own firmwares...

@tekka Thank you for great job on MYSBootloader. It works fine for me. Currently I'm testing it and have few questions.

• Please can you provide source code? Maybe then I can answer my questions myself :)
• Software signing doesn't work after firmware is uploaded. EEPROM is cleared. Is it possible to restore shared key HMAC after firmware is stored?
• Is possible to send firmware with signing to prevent loading from fake gateway? I thing signing of available firmware version and firmware CRC is enough ..?

Thank you for answers.