Not able to flash NFC code while Softdevice is loaded.

[Nikhilesh]

Hi!

I am trying to use the NFC "writable_ndef_msg" code along with the "ble_app_uart" code from SDK 15.0 with Softdevice s140 on nRF52840 DK.  I am using keil-MDK 5. But when I try to flash the NFC code when the softdevice is present, the Keil shows me error as "Cortex-M4". It works fine when the softdevice is removed. But when the softdevice is removed, the BLE code doesn't work. 

What should be the proper way in which I can have both softdevice and NFC codes co-exist along with BLE code?

[Ashish]

Hey,

Please take a look at the softdevice specs: https://www.nordicsemi.com/DocLib/Content/SoftDevice_Spec/s140/latest/SDS/s1xx/s140

 If you look at chapter 14, you can see the memory layout and usage. The softdevice is present starting from the lower address. 

In the NFC example, the ROM start address is set at 0x00 where the softdevice will be present. Probably that's the reason why you are getting an error while flashing when softdevice is present. You will need to change the starting ROM address to where the Softdevice has finished.

Here you can find the release notes for the softdevice you are using: 

https://www.nordicsemi.com/Software-and-Tools/Software/S140/Download#infotabs

In the release notes, you can find the Flash size requirement for the Softdevice. Change the starting ROM address to that location, and you should be able to flash the NFC example.

Update:
Should have linked this tutorial also,

devzone.nordicsemi.com/.../adjustment-of-ram-and-flash-memory

[Nikhilesh]

Hi Ashish, 

Thanks for the answer. I tried changing the ROM address of the NFC code. The code now gets flashed. But it not working. Nothing happens when I take my NFC reader close to the tag on the development kit (As per the code, the LED1 on the development kit should lit once it gets in the range of the reader. But nothing happens. Without softdevice it is working perfectly fine) Can you please suggest how to solve this issue? 

Thanks!

[Hung Bui]

Hi, 

How did you change the ROM setting to ? Have you tested with any BLE example in the SDK ? Please follow the ROM configuration in the example. Do you plan to use the softdevice ? 

I would suggest to copy your NFC code to a BLE example.