SamyGO

Yes,
Keep pressed "EXIT " key on the remote 15-20 seconds while BD is on...
I don't remember if you have to confirm in popup screen but if BD not restarting after 20 sec try press enter or arrow left and enter.
BTW , did you try to connect to TV from composite(analog) output ? ...this in case you changed some SM hdmi settings...

You could go to service or you can try to unbrick using this method as last option...

I did the same as you and bricked my BD-d8900a, I followed the eeprom reset instructions linked to in the previous post and with a bit of trouble I did get my BD back.

The eeprom is on the back side of the main board so this requires removing the powersupply and the main board.
Actually I had to fully (un)assemble the unit on the bench, (HD, Controll Panel,BD drive,WIFI) as it would not save all the setting.

I did the reset many times and in the end believe I may have had a corrupt NVRAM.

So this is what I think should work.
Strip unit and assemble on bench
Setup ruSamsungCommunicator on a pc
Connect AV to tv and set tv to AV, connect aerial port of BD
While shorting pins on eeprom turn power on, be very careful as the power supply has mains power now live...touch it and you wont be
The tv should show the smart blue ray logo keep pins shorted untill the tv looses av connection about 12 seconds after logo. You should now see the Set Language menu,country, time then tune and network, If you country isn?t there set to others, you can change it later once you set up the unit.
Get into service menu(remote info ruSamsungCommunicator factory) and do a EEPROM reset with the sub option to clear NVRAM (My unit would not save the model until I did this) System should restart and you have to go through and set up menus again, then go into service again and check model, tuner, region settings etc, when you have finished click the factory button twice on ruSamsungCommunicator , go into menu on BD and set your time and country settings. restart unit, try power off at wall as well.

Good Luck