This training center aligns Write MDQS in the
Write MDQ window at the DRAM. In this training mode, the controller pre-programs the
data buffer MPR registers with the expected pattern, issues write commands to load the
data into memory, and issues reads to the memory. The data buffer compares the read data
with the expected data and feeds back the result on the DQ bus. Calibration finds the
left and right edges of the MDQ valid window and centers MDQS in it.
Table 1. MWD Center Training Register
||Data Buffer MWD Taps [4:0]