Lance, This device has the capability to establish two separate JESD links if desired. There are some customers that would use the part in a redundancy application where if one link went down the other would still be working. In this mode, two SYNC's are required. SYNC_AB would be used for one link and SYNC_CD would be used for the other. Either one can be assigned to either link. These are CMOS level signals. The other sync signal, SYNCB, is an LVDS signal, and can be used by either link or both at the same time. Most customers will use this DAC with only one link. Register 0x49 (Config73) is used to assign the serdes lanes to a specific link. The GUI uses link 0 for most cases. In the 222 mode, this register is set to 0x00. Register 0x61 (Config97) is used to assign the SYNC's to a link. The 222 mode has this set to 0x211, which has SYNCB and SYNC_AB assigned to link 0 and SYNC_CD assigned to link 1. In this case, the user would not use SYNC_CD. In table 9, 2221 is showing 2 frames worth of data. each frame consists of 2 octets, which makes 1 sample per channel per frame. This table is confusing as some modes only show 1 frame (124) and others show 3 frames (821). Frames and lanes have nothing to do with number of links. Hope this helps. Regards, Jim
↧