Altera CPRI IP Core - Manual (Page 161)

Appendix B: Implementing CPRI Link Autorate Negotiation B–5
Autorate Negotiation From 9.8304 Gbps in Arria V GT Variations
December 2013 Altera Corporation CPRI MegaCore Function
User Guide
Table B–1 lists the frequencies at which you must drive the usr_clk and usr_pma_clk
input clocks in these CPRI IP core variations.
If your CPRI IP core Arria V GT variation is configured with the 9.8304 Gbps CPRI
line rate, it cannot negotiate down to a CPRI line rate of 0.6144 Gbps.
Table B–1. usr_ck and usr_pma_clk Frequencies at Different Target CPRI Line Rates
Target CPRI Line Rate (Gbps)
Frequency (MHz)
usr_clk usr_pma_clk
9.8304 245.76 122.88
6.144 153.6 76.8
4.9152 122.88 61.44
3.0720 76.8 153.6
2.4576 61.44 122.88
1.2288 30.72 61.44