Critical Issue
This problem affects DDR2 and DDR3, LPDDR2, QDR II, and RLDRAM II products.
The simulation example design may stop responding and issue warnings similar to the following:
# 3271428747 Note : Input frequency on DLL instance ddr3_ctrl_av_example_sim.e0.if0.dll0.dll_wys_m.inst
now matches with specified clock frequency.
# 3271457497 Warning : Input frequency violation on DLL instance ddr3_ctrl_av_example_sim.e0.if0.dll0.dll_wys_m.inst.
Specified input period is 2500 ps but actual is 3750 ps
The workaround for this issue is as follows:
- In a text editor, open the simulation example design top-level file (for example, corename_example_sim.v).
- In the simulation example design top-level file, change the reference clock BFM clock rate to match the required frequency in MHz.
For example, for the pll_ref_clk instance of altera_avalon_clock_source, replace.CLOCK_RATE
(32)
with
.CLOCK_RATE (32.765)
This issue will be fixed in a future version.