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"DCFIFO first written data: lost!"

AGaru1
Beginner
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Hi all.

 

I'm struggeling with a problem trying to write some datas into a DCFIFO.

The write signal (wrreq) is an output from a fsm like this:

 

......

 

    p_fifo_wr_fsm : process(wrclk, RST)

        begin

            if (RST = '1') then         

                wr_fifo_fsm_st              <= ST_IDLE;

                data                <= '0';

                wrreq               <= '0';   

            elsif rising_edge(wrclk) then   

                if (ENABLE = '0') then              

                                                                               wr_fifo_fsm_st                 <= ST_IDLE;

                                                                               data                <= '0';

                                                                               wrreq               <= '0';      

                else

                    case wr_fifo_fsm_st is

                        when ST_IDLE =>

                            if ((IN1 = '1') AND (IN2 = '1'))then

                                                                                                                              wr_fifo_fsm_st                <= ST_WR;

                                                                                                                              data                <= DATAIN;

                                                                                                                              wrreq               <= '1';

                            else

                                                                                                                              wr_fifo_fsm_st                <= ST_IDLE;

                                                                                                                              data                <= '0';

                                                                                                                              wrreq               <= '0';     

                            end if;

......

 

The problem is: the first data written into the fifo is missing when I try to read it.

The first read report the second written data.

The fifo is "no show ahead".

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KhaiChein_Y_Intel
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Hi,


Could you share the design QAR file, simulation result and testbench for investigation? To generate the QAR file, click on Project > Archive Project.


Thanks

Best regards,

KhaiY


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KhaiChein_Y_Intel
292 Views

Hi,


We do not receive any response from you to the previous question/reply/answer that I have provided. This thread will be transitioned to community support. If you have a new question, feel free to open a new thread to get the support from Intel experts. Otherwise, the community users will continue to help you on this thread. Thank you


Best regards,

KhaiY


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