Gearbox Latency Register (0x16) - 8.11 English

CPRI LogiCORE IP Product Guide (PG056)

Document ID
PG056
Release Date
2022-11-16
Version
8.11 English
Table 2-22: Gearbox Latency Register

Bits

Description

31:16

Receiver Gearbox Latency

15:0

Transmitter Gearbox Latency

This register is not used for Versal ACAP. The gearbox latency values should be read directly from the Versal GT Quad through an AXI interface.

In UltraScale-based cores operating at line rates of 8,110.08, 10,137.6, 12,165.12, and 24,330.24 Mb/s, the asynchronous gearbox is used to implement 64b66b encoding. The latency through the transmit and receive gearboxes is reported using this register.

See the UltraScale Architecture GTH Transceivers User Guide (UG576) [Ref 4] and UltraScale Architecture GTY Transceivers User Guide (UG578) [Ref 5] for more information on the asynchronous gearbox. The value is reported in units of 1/8 of a UI.