Runtime Switchable - 3.3 English

10G/25G High Speed Ethernet Subsystem Product Guide (PG210)

Document ID
PG210
Release Date
2020-12-16
Version
3.3 English

This configuration gives the flexibility to switch the line rate between 10G to 25G and vice-versa any time. To activate this feature, select the check box Runtime Switchable mode option in the Configuration tab. When this option is selected speed can be changed by using ch0_txrate and ch0_rxrate ports. Internally, the GT IP will perform required DRP writes to get the desired speed.

When this option is selected the *_trans_debug module will be present inside the *_pkt_gen_mon.v module of the example design. This *_trans_debug module is responsible for performing all the GT DRP write operations to switch the transceiver mode, that is, 10G to 25G or 25G to 10G. When you set the mode_change_* input signal High for two clock cycles and then make it Low, it starts the DRP write operation to the GT channel for the specific core and resets the specific core.

The DRP writes are done only for the channel. The QPLL0 of the common is fixed for the line rate 25G and the QPLL1 is fixed for the line rate 10G.

The state transition occurred during this process is shown in the following figure:

Figure 1. State Transition Diagram for Runtime Switchable DRP Operation without AN/LT

Figure 2. State Transition Diagram for Runtime Switchable DRP Operation with AN/LT