4 Replies Latest reply on Apr 25, 2019 11:15 PM by SrinathS_16

    Maximum endpoints of the FX3

    jach_4066871

      hi there,

           I want to know the maximum endpoints I can use in the FX3. In my project, there are 3 endpoints, 2 for in and 1 for out. Now I need add one endpoint for out and I had modified the number of endpoints in interface descriptor in the cyfxusbdscr.h and add descriptor information. What bothers me is that there are 4 endpoints but the FX3 failed connect the PC, and when I modified to the 3 endpoints, it works. And only the first three endpoints connect successfully, no matter which three endpoints I put forward. I know the maximum number of the endpoints isn't just 3 but what is the reason limits the number?HemanthR_06SrinathS_16

        • 1. Re: Maximum endpoints of the FX3
          SrinathS_16

          Hello,

           

          FX3 can support a maximum of 31 endpoints. Please share the descriptor file that you have used for enumerating 4 endpoints.

           

          Best regards,

          Srinath S

          • 2. Re: Maximum endpoints of the FX3
            jach_4066871

            Hello,

            Here are the descriptor files and the whole project. My device used the USB3.0 interface. At the beginning, more endpoints can be used but as the code increasing I can only use 3 endpoints. I want to know if the recourse of the RAM isn't enough or other reasons.

            Thanks.

            • 3. Re: Maximum endpoints of the FX3
              jach_4066871

              Hello,

              thanks for your support, I have tackled this problem. Because I didn't modify the length of the descriptor after I add a new endpoint descriptor. But I have  a new question, if I want the software FPGA configuration utility to recognize a new firmware whose VID/PID are not same as the ConfigFpgaSlaveFifoSync firmware. Do I just modify the myDevice and usbDevice of the GetDevice function in the C# express Edtion?

              The condition is that I have to recognize two software with one firmware, one is FPGA configuration utility and the other is a demo software whose function can't be modified. At the beginning, I use two set of the VID/PID of the firmeware to recognize two software, but it makes some trouble so I want to use one VID/PID to recognize these two software. 

              • 4. Re: Maximum endpoints of the FX3
                SrinathS_16

                Hello,

                 

                - Two software can access the same device using the VID/PID combination used in the device firmware.

                - Also, to distinguish devices with the same VID/PID, the device descriptor can be added with a serial number string descriptor and the same can be obtained on the host application using the CyUSB.USBDevice.SerialNumber string.

                 

                Best regards,

                Srinath S