7 Replies Latest reply on Dec 12, 2017 5:32 AM by satish.pandey_2992641

    packet loss in synchronous Slave FIFO mode

    mirzaii_h_1540796
              hello dear, according to "FX2LP DMB-TH TV Dongle Reference Design Guide" i made a board and every things was OK but for low frequency clocks (clear)but i needed near 27mhz clock for data input so i changed mode to synchronous Slave FIFO (Free Running MPEG CLK) and also made some little changes in firmware to support this mode ,i made some mpeg2 shape packets by a CPLD and also had a mpeg ts analyzer in the windows side to see packets,so 27mhz clock was OK and i saw mpeg2 ts packets in analyzer but until data rate near 50mbit/s .more than it i saw some packet loss near one per 1000,also it was not because of clock,also when i decrease clock to 13mhz but i see problem for data rate near 50mbit/s,so what is your idea?   
        • 1. Re: packet loss in synchronous Slave FIFO mode
          xchx

          Hello Comengin,

             

          From your description, you get data rate 50mbit/s when the IFCLK is 13mhz?

             

          Could you check the received data? the max bus width is 16bits, you can't get such high data rate with 13mhz.

             

           

             

          Best Regards,

             

          Nick

          • 2. Re: packet loss in synchronous Slave FIFO mode
            mirzaii_h_1540796

            Hello dear

               

            50mbit/s is so high?!!!! also i have checked before for 16bit bus width but also some miss packet ,i have seen some dvb usb cards based on FX2 chip also there is no cpld or fpga chip bitween FX2 and demodulator chip ,and they need more data rate than 50mbit/s,for example for dvb-s2, 8psk,sr=27500,fec=3/4,data rate is more than 60mbit/s ,so how they provide this bit rate without packet loss?

               

            Thanks.

            • 3. Re: packet loss in synchronous Slave FIFO mode
              xchx

              Hi Comengin,

                 

              Sorry for wrong information, it can get 50mbit/s,  how do you set the endpoint?  auto mode? fifo size?

                 

              Could you upload the firmware for check?

                 

              Best Regards,

                 

              Nick

              • 4. Re: packet loss in synchronous Slave FIFO mode
                mirzaii_h_1540796

                hello dear

                   

                the firmware is like what i found in "FX2LP DMB-TH TV Dongle Reference Design Guide" application note ,i only prepare it to work in "synchronous Slave FIFO" mode ,this is usbtv.c file:

                   

                also you can test it by your board an use a mpeg2ts data rate more than 50mbit/s to see the result.

                   

                thanks  very much

                • 5. Re: packet loss in synchronous Slave FIFO mode
                  xchx

                  Hi Comengin,

                     

                  1. Please use our streamer tool to test the data transfer speed, to see whether it's caused by host application, please download the FX3 SDK in below link, after install the fx3 SDK, you can find the streamer tool in path:C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\bin,

                     

                  FX3 driver and tool is compatible with FX2, please feel free to use it.

                     

                  http://www.cypress.com/documentation/software-and-drivers/ez-usb-fx3-software-development-kit

                     

                  2. you can configure the flag to indicate the fifo status to see whether the fifo is full when lose data happen.

                     

                  Best  Regards,

                     

                  Nick

                  • 6. Re: packet loss in synchronous Slave FIFO mode
                    mirzaii_h_1540796

                    hello dear, i came back again to this project

                       

                    anyway,a bout "FX2LP DMB-TH TV Dongle Reference Design Guide" application note,i made a dvb-s board based on this application note ,as i see the application not and its files provide only driver for 32bit windows ,i tested in several environment and the result :only in 32 bit XP was good ,for 64bit WIN7 windows doesn't accept diver and for 32bit WIN7 we have some lost in packets,as working good under XP i am sure the hardware has not problem.

                       

                    so my question: do you have plane to upgrade "FX2LP DMB-TH TV Dongle Reference Design Guide" application note ,to support driver for 64bit windows and also support LINUX, and right now what is your idea to use my board in 64bit windows

                       

                    thanks very much.

                    • 7. Re: packet loss in synchronous Slave FIFO mode
                      satish.pandey_2992641

                      Hello dear

                       

                      we are trying same thing but couldn't succeed to record TS,  we have removed tuner and demodulator from reference design and placed a 8 bit parallel  MPEG TS Connector to  give it   from external tuner.. but facing basic problem to record it.. is there any application available to record TS?

                       

                      here is detail about our efforts :

                       

                      We Are recently trying to capture parallel 8 bit Mpeg TS using CY7C68013A-56LTXC and get these MPEG TS to USB port.

                      for this purpose we  have referred design  FX2LP_DMB_TH_TV_Dongle   and prepared our OWN PCB without Tuner and de-modulator  , in our PCB we use to give Parallel TS on CY7C68013A , and using control center fprogramed pre build HEX file of USBTV &  MPEG_Free .

                       

                      after this PC is still not able to capture / record MPEG TS file . even in device tree OUR PCB detected as DMBTV and Cypress FX2lp Streamer Example device .

                       

                       

                      please suggest corrective action to help us to move out from this situation.

                       

                       

                      Regards

                      Satish P.