Delay through the GTHE4 transceiver consists of a variable component (barrel shift or TX and RX gearbox latency) and a fixed component. The fixed component is made up of the delay shown in the following table plus the additional line rate delay shown below.
| Block | Latency (UI) | |
|---|---|---|
| TX | 16-bit datapath cores (8b/10b) | 85 |
| 32-bit datapath cores (8b/10b) | 155 | |
| 64-bit datapath cores (64b/66b) | 176 | |
| RX | 16-bit datapath cores (8b/10b) | 134.5 |
| 32-bit datapath cores (8b/10b) | 248.5 | |
| 64-bit datapath cores (64b/66b) | 125.5 | |