The Edge board and RedBoard both have the Ambiq Secure Bootloader - though they are configured for different baud rates (in production Edge is set for 921600 and all the Artemis based boards are set for 115200)(As edge board and red board have different bootloaders)
From the factory the RedBoard will also have the SparkFun Variable Loader flashed on top of the ASB - but it is not protected in memory and will be overwritten when using the ASB.
(you can restore it by selecting ‘Ambiq Secure Bootloader’ as the ‘Programmer’ in Arduino and clicking ‘Burn Bootloader’)
When you say that you use uart_wired_update_sparkfun.py have you properly signed the update image using Ambiq’s scripts? It is easier to use the all-in-one script ‘ambiq_bin2board.py’ here: https://github.com/sparkfun/SparkFun_Ap … n2board.py
This makes me think you are calling each of the scripts the same way? There are differences in the arguments to the ASB and the SVL. You can see examples of that here:${PROGRAMMER_SCRIPT} -b 115200 -f $(CONFIG)/main_nonsecure_wire.bin -v -t 0.50 $(SERIAL_PORT)
https://github.com/sparkfun/Arduino_Apo … #L135-L136
https://github.com/sparkfun/Arduino_Apo … #L166-L167
Also bear in mind the fact that your code needs to be linked appropriately for which bootloader you are using - code for the ASB should begin at address 0xC000 while code for the SVL should begin at 0x10000