The data that is written to the SDRAM during training is created within the data slice. The following data pattern options are available:
- Clock pattern - An alternating pattern of "1" and "0" is applied to each DQ/DM. The phase of the 1/0 pattern is identical on the DQ/DM pins.
- LFSR pattern - The same LFSR pattern that is used for data loopback can be applied to the DQ/DM pins. The LFSR is reset at the start of the pattern and each burst of data is different according to the progression of the LFSR.
- User defined pattern - A user defined pattern can also be applied to the DQ/DM pins. Independent data for each bit covering a full burst of 16 can be loaded into register fields to supply the training data. The same data pattern is repeated for every burst. The pattern is defined through the following fields:
- DDRSS_PHY_36[31-0] PHY_USER_PATT0_0
- DDRSS_PHY_292[31-0] PHY_USER_PATT0_1
- DDRSS_PHY_548[31-0] PHY_USER_PATT0_2
- DDRSS_PHY_804[31-0] PHY_USER_PATT0_3
- DDRSS_PHY_37[31-0] PHY_USER_PATT1_0
- DDRSS_PHY_293[31-0] PHY_USER_PATT1_1
- DDRSS_PHY_549[31-0] PHY_USER_PATT1_2
- DDRSS_PHY_805[31-0] PHY_USER_PATT1_3
- DDRSS_PHY_38[31-0] PHY_USER_PATT2_0
- DDRSS_PHY_294[31-0] PHY_USER_PATT2_1
- DDRSS_PHY_550[31-0] PHY_USER_PATT2_2
- DDRSS_PHY_806[31-0] PHY_USER_PATT2_3
- DDRSS_PHY_39[31-0] PHY_USER_PATT3_0
- DDRSS_PHY_295[31-0] PHY_USER_PATT3_1
- DDRSS_PHY_551[31-0] PHY_USER_PATT3_2
- DDRSS_PHY_807[31-0] PHY_USER_PATT3_3
- DDRSS_PHY_40[15-0] PHY_USER_PATT4_0
- DDRSS_PHY_296[15-0] PHY_USER_PATT4_1
- DDRSS_PHY_552[15-0] PHY_USER_PATT4_2
- DDRSS_PHY_808[15-0] PHY_USER_PATT4_3
These patterns can be used in any combination and if multiple patterns are requested, the final results are based on the largest leading edge found and the smallest trailing edge found across the patterns selected.