Start Debug Session is fail

Dear All,

  I suffer a problem. I am starting debug mode with my FPGA which includes ARM-M0.

I already set LOAD %L INCREMENTAL  in my Ram.ini, but it is fail during staring debug. 

  The error message is as below

A). I don't understand why to access memory is fail ?  But if 

1.

    Step 1:  Press download icon to download SW code to code memory

    Step 2:  To start debug is OK

2.

    Step 1: Enable Utility > Update Target before Debugging

    Step 2: build code

    Step 3: To start debug is also OK.

According to the experiments from 1 and 2, I should download code before staring debug, but I don't understand why it is fail for  LOAD %L INCREMENTAL  in my Ram.ini. The error message is 

       *** error 122: AGDI: memory read failed (0xFFFFFFFE)
       Cannot access Memory (@ 0xfffffffe, Read, Acc Size: 2 Byte)

B). What is address 0xFFFFFFFE for M0?

Thanks for you help.

BR,

Eddie