linkstation pro stuck in EM mode after hard drive change

[Ke20]

Hi,

My linkstation pro 1to hdd died and so I tried to replace it with a new hdd, and doing the tftp boot recovery procedure.
This procedure work as the 2 files get pulled but after the blue led is still blinking and there is no way to access the linkstation via lsupdater

So i tried as other suggested to connect the drive by usb and  I formatted it  using gpt and created a partiton ext3 on the drive with the /boot folder and the initrd.buffalo and uimage.buffalo inside. This partiton has the boot flag set

The linkstation boot and blink red 6 times and is still not accessible via lsupdater. tftp as the same result as before

What is the minimal partiton configuration to get the linkstation boot out of em mode ? do i need to put the hddrootfs in a partition also ?

Thanks a lot for your help!