How to flash hex file using dfu in nrf Tool box application

Question

hi,
i am working on blinky example code. i was build the code and generated hex file using Eclipse IDE. i have nrf51822 ble module. 
 want to flash the hex file using dfu in nrf tool box mobile application(through bluetooth). i am able to select the hex file but unable flash hex file.
because it is(nrf tool box app) displaying dfu service not found.
is dfu service required to add existing blinky example.
otherwise any dfu examples are there in sdk examples which can possible to flash code through nrf tool box app.

Keton · Accepted Answer

In order for DFU to work you have to flash bootloader and softdevice onto your board. Also as you are using custom board it's important that you define buttons and leds as by default bootloader is triggered by holding button4 and reseting the board. For a quick debug you may try to connect buttons and leds to the same pins as in Nordic nRF51-DK so no code changes will be necessary. Assuming that you are using SDK11 you should: 
 
 do a full chip erase in nrfGo Studio or using nrfjprog -e 
 flash S130v2 hex file 
 flash bootloader hex file examples\dfu\bootloader\hex\dfu_dual_bank_ble_s130_pca10028 
 after board reset equivalents of LEDs 1 and 3 should be on. Board is stuck in bootloader mode because there's no application flashed. There should be bootloader peripheral device 'DfuTarg' on you BLE scanner 
 using nRFConnect app for android flash examples\dfu\ble_dfu_send_hex	est_images_update_nrf51\dfu_test_app_hrm_s130_w_dfu.zip : 
 
 
 connect to 'DfuTarg' device there 
 should be DFU button next to 
 disconnect button, press it select update .zip file and press start 
 there should be graph showing update progress 
 
 
 after operation completes there should be Nordic_HRM peripheral 
 if you connect to it there should be a DFU service and DFU button should be active so you can try to flash something else. 
 
 For a first time approach I strongly recommend connecting button to DK button 4 pin and all 4 LEDs. Also try SDK11 as it's more automated than in case of 12. After you make it work you may try to switch to SDK12 where there's no automated way of entering bootloader from app so far and you need to have custom bootloader build with you crypto keys.