Ble_app_uart soft device is not flashing

[SamPenn]

Hello, I'm fairly new to embedded software. I'm trying to flash the ble_app_uart program from the command line (windows 10 / nRF5_sdk_15.3.0_59ac345 / nRF52840 / Eclipse IDE).

My commands are as follows:

armgcc/>make

armgcc/>nrfjprog --family nRF52 -e

armgcc/>nrfjprog --family nRF52 --program _build/nrf52840_xxaa.hex

armgcc/>nrfjprog --family nRF52 -r

all commands pass without a sweat, but then nothing changes on the board, no blinking nothing. When I copy over ble_app_uart/hex/ble_app_uart_pca10056_s140.hex directly into the jlink folder, it starts running. Am I missing a step? Should I be flashing this hex file and not the one found in _build? If that is the case how do I go about editing the code inside of this hex file?

[Simon]

The difference between the hex file inside the build folder and the one inside ble_app_uart/hex/ is that the former does not include a SoftDevice and the latter does. In order to use the hex file inside the build folder you need to flash the SoftDevice first.

Best regards,

Simon

[SamPenn]

Is there a specific command that I need or do I just use nrfjprog --program hex/_____ then _build/____. Cause when I flash the build after the soft device I get:
"ERROR: The area to write is not erased."

[Simon]

Try to run these commands:

nrfjprog -f nrf52 --program $(SDK_ROOT)/components/softdevice/s140/hex/s140_nrf52_6.1.1_softdevice.hex --sectorerase

nrfjprog -f nrf52 --reset 

Best regards,

Simon

[SamPenn]

I tried that and I still get the error when I try to flash the _build/nrf52840_xxaa.hex. 

edit: I put sector erase after my second command as well that did the trick. 

Thank you so much for your time Simon! You have been incredibly helpful!