How can I measure latency of my TLPs through the block?
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The latency through the TRN interface will depend on the following:
For this reason, to get the most accurate latency numbers, it is best to simulate the core under your expected conditions and your core configuration. It is best to pull the following three signals into your simulation:
Measure the time between the assertion of trn_tsof_n and when the "Start TLP" Special Character is shown on the TXDATA of the transceiver. Usually, it will be on lane 0 or for an x8 link it can be on lane 0 or lane 4.The "Start TLP" Special Character is K27.7 = 0xFB.CHARISK will assert at this time indicating the 0xFB K character.Revision History