4 Replies Latest reply on Mar 13, 2018 5:49 AM by geethadiwakargeetha_2778001

    FX3S GPIF 2 INTERFACE

    geethadiwakargeetha_2778001

      HI,

      I am using fx3s in gpif 2 interface with an image sensor.

      my image sensor pins are only 10.

      my fx3 firmware is configured for 16bit gpif2 in gpif 2 designer tool.

      from data0 to data9 is connected to an image sensor.

      remaining data10 to data15 are not connected.

      can i use these unconnected p port pins as normal GPIO's????

       

      any changes regarding data value in the (p port to u port) commit buffer??

       

      thank you.....

        • 1. Re: FX3S GPIF 2 INTERFACE
          srdr

          Geetha,

           

          GPIF works with set of bus interfaces: 8-bit, 16-bit, 24-bit, 32-bit.

           

          If the GPIF is configured to work as 16-bit, and you have connected only 10 lines to GPIF, the GPIF will sample all 16 lines and store it in the buffer.

           

          So the unconnected lines will be sampled as floating data. So you have to take care of them (data comes through un-connected lines) in the host application.

           

          Answering to question:

           

          Can not use unconnected pins as normal GPIOs.

           

          Regards,

          Sridhar

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          • 2. Re: FX3S GPIF 2 INTERFACE
            geethadiwakargeetha_2778001

            Hi sridhar,

            thank you for replying...

             

            So the unconnected lines will be sampled as floating data. So you have to take care of them (data comes through un-connected lines) in the host application.

            -->

            we grounded these unconnected pins through resistor.

            is it effect in the buffer?

             

             

            Can not use unconnected pins as normal GPIOs.

            -->

            i need some gpios for other application,so planned to use these unconnected data lins(and also reguire 16 bit interface only),is it possible to use these pins by making these pins as pulled down or pulled up?

            please let me know

             

            thank you

            • 3. Re: FX3S GPIF 2 INTERFACE
              srdr

              If you ground unconnected pins, those will be sampled as zero and stored in the buffer.

               

              You can not touch unconnected pins even though you pulled up or down to use them as normal as GPIOs.

               

              Refer the data sheet pin description with 16-bit GPIF, it shows the available GPIOs for apart from these 16-bit GPIF bus lines.

               

              Do you need more GPIOs than what is stated in the data sheet?

               

              Note that if you are not using any UART, I2C, SPI, I2S blocks, you can use those PINs as GPIOs using GPIOOverride API.

               

              Regards,

              Sridhar

              1 of 1 people found this helpful
              • 4. Re: FX3S GPIF 2 INTERFACE
                geethadiwakargeetha_2778001

                Hi sir,

                i concluded that when we are using 16 bit interface,the unused pins(among 16 data pins) should be grounded or unconnected,they can't be used as normal GPIO even with gpiooverride API.

                 

                thank you...

                 

                I am using 16 bit interface with slavefifo.In my application we are using stream in mode(writing data to fx3 from fpga),using corresponding flag a (full/empty flag) and flag b(partial flag) but not using flag C and D(we are not reading any data from fx3 to fpga and don't required),is above condition will apply for flag C and D?can't use gpios?with gpiooveride?

                 

                let me know sir,we need gpios for our application,we are using UART,I2C,SD CARD interface also