The TX must observe the LBUS rules that are required for compliance to the Interlaken Protocol Definition, Revision 1.2 as well as AMD implementation-specific requirements.
If a burst rule violation has occurred, the signal stat_tx_burst_err
is asserted. You must ensure that the rules governing the scheduling of bursts are
observed according to the LBUS width in the particular implementation. In
particular, the segmented LBUS protocol should be given careful reading.
One common problem is that you have written data in such a way that more than the maximum number of allowed Burst Control Words are generated during one clock cycle. Carefully review the segmented LBUS rules. Take care that an SOP or channel change does not occur in the same cycle as an implied Burst Control Word resulting from BurstMax having been reached.
This can be avoided by implementing the Enhanced Scheduling Algorithm, which makes
use of the signal tx_bctlin to force Burst Control Words in such a
way as to avoid more than the maximum allowed number in one clock cycle.
In summary, Burst Control Words can be implied or generated by the following cases:
- BurstMax reached (implied)
- SOP (implied)
- Channel Change (implied)
- bctlin assertion (forced)