Arria V DQS

Dear all,

I use ArriaV FPGA. On FPGA, I have a bi-directional bus which can be used in asynchronous and DDR mode.

In DDR mode, I use DQs (Data strobe) to synchronize data for read request.

I want set manually the delay (D3_1) to read correctly the input data because the delay depend of the using clock .

When I use the assignement editor, i have this warning is appear:

I set DQS pin with D3 Delay (I/O buffer to internal cells) with 4 value.

Critical Warning (176425): Ignored Input Delay from Pin to Internal Cells logic option assignment (setting = 4) to input or bidirectional pin DQS because all of its fan-outs already have assignments of a different delay value (setting = 0).

In the compilation report, D3_0 is equal to 0.

Then I use RPE tool and on the DQS PAD, I set the 4 value in D3 Delay Chain 0. After I click on the check and save all netlist changes. Quartus run Fitter and assembler. There is no warning and error.

In the compilation report, I don't have access to delay chains report. I'm not sure that Delay chains are programmed correctly.

Do you have any idea to set properly the delay timing D3_0?

Thanks in advance for your help.