It is not recommended to flash bootloaders on your device unless necessary. When flashing bootloaders, make sure the model number matches the device you are flashing. Also, always use a new cable without any wiggle room or cable damage.
To get into download mode to use Odin or Heimdall:
Remove and replace battery.
hold Volume Down & Home then press power while continuing to hold power.
You can now use Odin or Heimdall to flash a stock ROM package.
The Fix for Hard Bricks:
In the event that you cannot get to download mode, please contact me. I am developing a boot-from-sdcard fix for bricked Galaxy Cameras based on the methods used in i9300 here: http://forum.xda-developers.com/show...php?p=34139922. The hardware mod must be located to boot Odin Mode (Loke Daemon) the SDCard. JTAG will not work on Exynos 4412 devices.
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