Calibration fail with HP DDR2 controller

hi

im using the HP DDR2 controller with 5 discrete DDR2 components (4+1 ECC)

i get an error during calibration..

when i looked at the write & read cycles i saw that i write the same pattrern as the simulation but i cant read the exact data. the simulation is OK but in real life i read one bit less at the start of the data & one bit less at the end..

ive gone over all the controls (cas,RAS,CS,CKE,ODT) & the CK,CK~..

i really am stuck..

is there any idea??

im attaching the wr & rd cycles during calibration - will attach later

thnx