Achronix Speedster22i SerDes - Manual (Page 81)

• All clocks from SerDes lanes 0 to 14 on the South Side of the Chip enter the far
SouthWest clock region.
• All clocks from SerDes lanes 20 to 31 on the South Side of the Chip enter the far
SouthEast clock region.
• All clocks from SerDes lanes 15 to 19 on the South Side of the Chip enter BOTH the
far SouthWest and far SouthEast clock regions. Avoid using these lanes if possible.
• As a rule of thumb, you will always need at least 1 system clock and 1 SBUS clock in
each clock region. So the total number of SerDes clocks is effectively limited to 14
clocks.
UG028, July 1, 2014 81