Nordic S210 Softdevice Debugging

Hi, 

I'm currently trying to get Nordic's HR example running on my dev board, I've got the S210 soft device installed (v 4.0.0) and I'm running version 7.2.0 of their SDK. The code downloads to the correct location on the device and I enter the debugger normally with no issue, when I allow the code to run freely at some point I enter the soft device and the debugger halts at line 210 with the following instructions in the disassembly view.

    20B4        movs r0, #0xB4

The program then puts 0xFFFFFFFE into the PC register and stops working. I'm not really too sure where to go from here, and any help at all would be appreciated!