You mentioned you measured with oscilloscope processor read the BLDK firmware from flash device. Can you see how many read cycles? After some initial instructions there is an out to port 80 informing boot has been started. In case this does not happen then also considering the other 4 boards are working correctly that the processor is not assembled correctly.
Considering you have a proto series of 5 pieces then your production soldering process has not been optimized yet. You might perform a visual check (view from the side) if the solder balls are shining. If this is not the case you might try a second time through the soldering oven.
You might also use the XDP debugger (using JTAG) to check the processor.
Good luck with getting also this board to work.
Frank van Weerdenburg
Thank you for your advices. Initial cycles take about 250 msec - it is too short. In working boards it takes about 1 second. Whence processor know that does not need to read the rest of the flash? We tried to re-solder the processor and memory (8 x 2gbit ddr2 ) the 2 times already. Soldering look very good, but we don't have X-ray to check exactly. We have dediprog SF100 for loading flash not for emulation. What XDP debugger can show in this case?