****************DFU_BOOTLOADER Settings for nRF51822 and nRF51422 chip (128 Kb & 256 Kb both)*********************

1. goto directory "nRF51_SDK_10.0.0_dc26b5e\examples\dfu\bootloader" and then open file "dfu_gcc_nrf51.ld" 

2. settings for 128Kb flash and 16kb ram

   >FLASH (rx) : ORIGIN = 0x1C000, LENGTH = 0x3C00                    /*BOOTLOADER's code region as per memory size*/
   >RAM (rwx) :  ORIGIN = 0x20002000, LENGTH = 0x1380                 /*RAM region start address and RAM size*/
   >NOINIT (rwx) :  ORIGIN = 0x20003380, LENGTH = 0x80                /*NOINIT ORIGIN = 0x20002000 + 0x1380 and 0x80 size*/
   >BOOTLOADER_SETTINGS (rw) : ORIGIN = 0x0001FC00, LENGTH = 0x0400   /*BOOT..SETTING START = 0x1C000 = 0x3C00*/
   >UICR_BOOTLOADER (r) : ORIGIN = 0x10001014, LENGTH = 0x04

   settings for 256Kb flash and 32kb ram

   >FLASH (rx) : ORIGIN = 0x3C000, LENGTH = 0x3C00                    /*BOOTLOADER's code region as per memory size*/
   >RAM (rwx) :  ORIGIN = 0x20002C00, LENGTH = 0x5380                 /*RAM region start address and RAM size*/
   >NOINIT (rwx) :  ORIGIN = 0x20007F80, LENGTH = 0x80                /*NOINIT ORIGIN = 0x20002000 + 0x1380 and 0x80 size*/
   >BOOTLOADER_SETTINGS (rw) : ORIGIN = 0x0003FC00, LENGTH = 0x0400   /*BOOT..SETTING START = 0x1C000 = 0x3C00*/
   >UICR_BOOTLOADER (r) : ORIGIN = 0x10001014, LENGTH = 0x04

3. And then Save and Exit.

4. goto directory "nRF51_SDK_10.0.0_dc26b5e\components\libraries\bootloader_dfu" and then open file "dfu_types.h"

5. settings for 128Kb flash and 16kb ram

   >#define BOOTLOADER_REGION_START         0x0001C000 
   >#define BOOTLOADER_SETTINGS_ADDRESS     0x0001FC00

   settings for 256Kb flash and 32kb ram

   >#define BOOTLOADER_REGION_START         0x0003C000
   >#define BOOTLOADER_SETTINGS_ADDRESS     0x0003FC00

6. And then Save and Exit. After then compile and run on Eclipse gcc tool chain setup...