Visible to Intel only — GUID: nik1411442180519
Ixiasoft
Visible to Intel only — GUID: nik1411442180519
Ixiasoft
3.16. Auto-Rate Negotiation
If you turn on Enable line bit rate auto-negotiation in the CPRI parameter editor, the auto-rate negotiation control and status interface is available. The Stratix® 10 E-tile and Agilex® 7 E-tile design example variants support the auto-rate negotiation feature in simulation testbench and hardware. The CPRI IP provides support for dynamically changing the CPRI line bit rate. The design example shows how to switch from highest CPRI rate to the lowest CPRI rate that you specify in IP configuration. However, you must add more logic such as T1 interval, to be compliant to auto negotiation in CPRI protocol. You control the process through the auto-rate negotiation control and status interface or the BIT_RATE_CONFIG register at offset 0x0C.
Signal Name |
Direction |
Description |
---|---|---|
nego_bitrate_in[5:0] | Input | CPRI line bit rate to be used in next attempt to achieve frame synchronization, encoded according to the following valid values:
This signal has higher priority than the bit_rate field in the BIT_RATE_CONFIG register at offset 0x0C. When this signal has the value of 6'b000000, the CPRI IP core responds to the register field. |
nego_bitrate_out[5:0] | Output | Reflects the current actual CPRI line bit rate. |