BTW it is not possible to single step nrf52 code once bluetooth is running, the softdevice has strict timing requirements so you cannot pause such code and continue, you can have breakpoint to investigate single issue but then you need to reboot.
However if you run NRF.sleep() to disable bluetooth before attaching debugger or remove BLUETOOTH module from build it should work.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
The key is the elf file, that one contains both the binary and symbols and links to source code files. Never used SES but quick googling gave this https://forum.segger.com/index.php/Thread/3487-Debug-elf-built-by-external-gcc-toolchain/
BTW it is not possible to single step nrf52 code once bluetooth is running, the softdevice has strict timing requirements so you cannot pause such code and continue, you can have breakpoint to investigate single issue but then you need to reboot.
However if you run
NRF.sleep()
to disable bluetooth before attaching debugger or remove BLUETOOTH module from build it should work.