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 performs required DRP writes to get the intended speed.
When this option is selected, the *_trans_debug module is 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. The
mode 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.
- For the switching operation, you must copy the
trans_debugmodule into your design. - The 10G/25G Ethernet Subsystem generates an Example
Design with the GT configured as:
- RX Equalization Mode
- Auto
- Insertion Loss at Nyquist (dB)
- 30
-
If the Receiver Options configuration differs from the default settings in the 10G/25G Ethernet Subsystem IP with runtime switch example design, the
trans_debugDRP values in the example file can need modification. You must edit these settings based on the specific equalization needs of your design.
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: