Hello, I have just started. Attached in my program. And "I think" it shud put all GPIO high all the time. Ref : [1] https://files.ettus.com/manual/page_gpio_api.html [2] http://lists.ettus.com/pipermail/usrp-users_lists.ettus. com/2015-August/015458.html And hence I attached the '+' of LED to GPIO-4 and '-' of LED to Pin 10. I compile my script with g++ basic.cpp -luhd -o rx My script works, but LED never glows. What wrong I am doing. You can jump to line 64 to see the GPIO stuff. Regards -- -- Sumit kumar Doctoral Student, UPMC Eurecom, BIOT France

Hi Sumit, I don't have the specifications handy, however the GPIOs are driven directly from the FPGA, and do not have a lot of output current. Most likely not enough to drive the LED. It is important not to draw too much power from the GPIOs as it could potentially damage the FPGA output. I would recommend using a transistor in line to drive the LED from another power source. There are many guides online covering this topic. I would also recommend to use an oscilloscope to verify that your GPIO pin is working correctly. Regarding your code, using the 0xFF bitmask, it should turn all of the GPIOs on. Regards, Nate Temple > On Feb 8, 2017, at 12:32 PM, Sumit Kumar via USRP-users <usrp-users@lists.ettus.com> wrote: > > Hello, > > I have just started. Attached in my program. And "I think" it shud put all GPIO high all the time. > > Ref : > > [1] https://files.ettus.com/manual/page_gpio_api.html > > [2] http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/2015-August/015458.html > > > And hence I attached the '+' of LED to GPIO-4 and '-' of LED to Pin 10. > > I compile my script with > > g++ basic.cpp -luhd -o rx > > My script works, but LED never glows. > > What wrong I am doing. > > You can jump to line 64 to see the GPIO stuff. > > Regards > > -- > -- > Sumit kumar > Doctoral Student, UPMC > Eurecom, BIOT > France > > <a.png><basic.cpp>_______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com

hello Sumit, b2xx GPIO output is 3.3V, but current is unspecified. By measuring output current you can make sure if it's possible for your led. you can use a transistor (that can be activated by that amount of current) as Nate said, or use a level shifter. best, enes unal 9 Şub 2017 Per, 09:40 tarihinde, Nate Temple via USRP-users < usrp-users@lists.ettus.com> şunu yazdı: > Hi Sumit, > > I don't have the specifications handy, however the GPIOs are driven > directly from the FPGA, and do not have a lot of output current. Most > likely not enough to drive the LED. It is important not to draw too much > power from the GPIOs as it could potentially damage the FPGA output. > > I would recommend using a transistor in line to drive the LED from another > power source. There are many guides online covering this topic. > > I would also recommend to use an oscilloscope to verify that your GPIO pin > is working correctly. > > Regarding your code, using the 0xFF bitmask, it should turn all of the > GPIOs on. > > > Regards, > Nate Temple > > > > > > > On Feb 8, 2017, at 12:32 PM, Sumit Kumar via USRP-users < > usrp-users@lists.ettus.com> wrote: > > > > Hello, > > > > I have just started. Attached in my program. And "I think" it shud put > all GPIO high all the time. > > > > Ref : > > > > [1] https://files.ettus.com/manual/page_gpio_api.html > > > > [2] > http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/2015-August/015458.html > > > > > > And hence I attached the '+' of LED to GPIO-4 and '-' of LED to Pin 10. > > > > I compile my script with > > > > g++ basic.cpp -luhd -o rx > > > > My script works, but LED never glows. > > > > What wrong I am doing. > > > > You can jump to line 64 to see the GPIO stuff. > > > > Regards > > > > -- > > -- > > Sumit kumar > > Doctoral Student, UPMC > > Eurecom, BIOT > > France > > > > <a.png><basic.cpp>_______________________________________________ > > USRP-users mailing list > > USRP-users@lists.ettus.com > > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > > > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >

Ok, I got it. I think I will use oscilloscope then! On Thu, Feb 9, 2017 at 8:33 AM, Enes ÜNAL <aenesunal@gmail.com> wrote: > hello Sumit, > > b2xx GPIO output is 3.3V, but current is unspecified. By measuring output > current you can make sure if it's possible for your led. > > you can use a transistor (that can be activated by that amount of current) > as Nate said, or use a level shifter. > > best, > enes unal > > > 9 Şub 2017 Per, 09:40 tarihinde, Nate Temple via USRP-users < > usrp-users@lists.ettus.com> şunu yazdı: > >> Hi Sumit, >> >> I don't have the specifications handy, however the GPIOs are driven >> directly from the FPGA, and do not have a lot of output current. Most >> likely not enough to drive the LED. It is important not to draw too much >> power from the GPIOs as it could potentially damage the FPGA output. >> >> I would recommend using a transistor in line to drive the LED from >> another power source. There are many guides online covering this topic. >> >> I would also recommend to use an oscilloscope to verify that your GPIO >> pin is working correctly. >> >> Regarding your code, using the 0xFF bitmask, it should turn all of the >> GPIOs on. >> >> >> Regards, >> Nate Temple >> >> >> >> >> >> > On Feb 8, 2017, at 12:32 PM, Sumit Kumar via USRP-users < >> usrp-users@lists.ettus.com> wrote: >> > >> > Hello, >> > >> > I have just started. Attached in my program. And "I think" it shud put >> all GPIO high all the time. >> > >> > Ref : >> > >> > [1] https://files.ettus.com/manual/page_gpio_api.html >> > >> > [2] http://lists.ettus.com/pipermail/usrp-users_lists. >> ettus.com/2015-August/015458.html >> > >> > >> > And hence I attached the '+' of LED to GPIO-4 and '-' of LED to Pin 10. >> > >> > I compile my script with >> > >> > g++ basic.cpp -luhd -o rx >> > >> > My script works, but LED never glows. >> > >> > What wrong I am doing. >> > >> > You can jump to line 64 to see the GPIO stuff. >> > >> > Regards >> > >> > -- >> > -- >> > Sumit kumar >> > Doctoral Student, UPMC >> > Eurecom, BIOT >> > France >> > >> > <a.png><basic.cpp>_______________________________________________ >> > USRP-users mailing list >> > USRP-users@lists.ettus.com >> > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >> >> >> _______________________________________________ >> USRP-users mailing list >> USRP-users@lists.ettus.com >> http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >> > -- -- Sumit kumar Doctoral Student, UPMC Eurecom, BIOT France

Hi Sumit, Following up on this, as detailed here [1] the GPIOs are LVCMOS33 outputs with pull-ups. The strength for LVCMOS and LVTTL on Spartan 6 is 12 mA if not otherwise specified. Regards, Nate Temple [1] - https://github.com/EttusResearch/fpga/blob/maint/usrp3/top/b200/gpio.ucf > On Feb 9, 2017, at 1:29 AM, Sumit Kumar <cogwsn@gmail.com> wrote: > > Ok, I got it. I think I will use oscilloscope then! > > > > On Thu, Feb 9, 2017 at 8:33 AM, Enes ÜNAL <aenesunal@gmail.com> wrote: > hello Sumit, > > b2xx GPIO output is 3.3V, but current is unspecified. By measuring output current you can make sure if it's possible for your led. > > you can use a transistor (that can be activated by that amount of current) as Nate said, or use a level shifter. > > best, > enes unal > > > 9 Şub 2017 Per, 09:40 tarihinde, Nate Temple via USRP-users <usrp-users@lists.ettus.com> şunu yazdı: > Hi Sumit, > > I don't have the specifications handy, however the GPIOs are driven directly from the FPGA, and do not have a lot of output current. Most likely not enough to drive the LED. It is important not to draw too much power from the GPIOs as it could potentially damage the FPGA output. > > I would recommend using a transistor in line to drive the LED from another power source. There are many guides online covering this topic. > > I would also recommend to use an oscilloscope to verify that your GPIO pin is working correctly. > > Regarding your code, using the 0xFF bitmask, it should turn all of the GPIOs on. > > > Regards, > Nate Temple > > > > > > > On Feb 8, 2017, at 12:32 PM, Sumit Kumar via USRP-users <usrp-users@lists.ettus.com> wrote: > > > > Hello, > > > > I have just started. Attached in my program. And "I think" it shud put all GPIO high all the time. > > > > Ref : > > > > [1] https://files.ettus.com/manual/page_gpio_api.html > > > > [2] http://lists.ettus.com/pipermail/usrp-users_lists.ettus.com/2015-August/015458.html > > > > > > And hence I attached the '+' of LED to GPIO-4 and '-' of LED to Pin 10. > > > > I compile my script with > > > > g++ basic.cpp -luhd -o rx > > > > My script works, but LED never glows. > > > > What wrong I am doing. > > > > You can jump to line 64 to see the GPIO stuff. > > > > Regards > > > > -- > > -- > > Sumit kumar > > Doctoral Student, UPMC > > Eurecom, BIOT > > France > > > > <a.png><basic.cpp>_______________________________________________ > > USRP-users mailing list > > USRP-users@lists.ettus.com > > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > > > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > > > > -- > -- > Sumit kumar > Doctoral Student, UPMC > Eurecom, BIOT > France >

Hi Nate, I tried with a 3mm LED which glows up with less than 12mA. Its worked. Thanks ! Sumit On Thu, Feb 9, 2017 at 6:08 PM, Nate Temple <nate.temple@ettus.com> wrote: > Hi Sumit, > > Following up on this, as detailed here [1] the GPIOs are LVCMOS33 outputs > with pull-ups. The strength for LVCMOS and LVTTL on Spartan 6 is 12 mA if > not otherwise specified. > > Regards, > Nate Temple > > [1] - https://github.com/EttusResearch/fpga/blob/maint/ > usrp3/top/b200/gpio.ucf > > > > On Feb 9, 2017, at 1:29 AM, Sumit Kumar <cogwsn@gmail.com> wrote: > > > > Ok, I got it. I think I will use oscilloscope then! > > > > > > > > On Thu, Feb 9, 2017 at 8:33 AM, Enes ÜNAL <aenesunal@gmail.com> wrote: > > hello Sumit, > > > > b2xx GPIO output is 3.3V, but current is unspecified. By measuring > output current you can make sure if it's possible for your led. > > > > you can use a transistor (that can be activated by that amount of > current) as Nate said, or use a level shifter. > > > > best, > > enes unal > > > > > > 9 Şub 2017 Per, 09:40 tarihinde, Nate Temple via USRP-users < > usrp-users@lists.ettus.com> şunu yazdı: > > Hi Sumit, > > > > I don't have the specifications handy, however the GPIOs are driven > directly from the FPGA, and do not have a lot of output current. Most > likely not enough to drive the LED. It is important not to draw too much > power from the GPIOs as it could potentially damage the FPGA output. > > > > I would recommend using a transistor in line to drive the LED from > another power source. There are many guides online covering this topic. > > > > I would also recommend to use an oscilloscope to verify that your GPIO > pin is working correctly. > > > > Regarding your code, using the 0xFF bitmask, it should turn all of the > GPIOs on. > > > > > > Regards, > > Nate Temple > > > > > > > > > > > > > On Feb 8, 2017, at 12:32 PM, Sumit Kumar via USRP-users < > usrp-users@lists.ettus.com> wrote: > > > > > > Hello, > > > > > > I have just started. Attached in my program. And "I think" it shud put > all GPIO high all the time. > > > > > > Ref : > > > > > > [1] https://files.ettus.com/manual/page_gpio_api.html > > > > > > [2] http://lists.ettus.com/pipermail/usrp-users_lists. > ettus.com/2015-August/015458.html > > > > > > > > > And hence I attached the '+' of LED to GPIO-4 and '-' of LED to Pin 10. > > > > > > I compile my script with > > > > > > g++ basic.cpp -luhd -o rx > > > > > > My script works, but LED never glows. > > > > > > What wrong I am doing. > > > > > > You can jump to line 64 to see the GPIO stuff. > > > > > > Regards > > > > > > -- > > > -- > > > Sumit kumar > > > Doctoral Student, UPMC > > > Eurecom, BIOT > > > France > > > > > > <a.png><basic.cpp>_______________________________________________ > > > USRP-users mailing list > > > USRP-users@lists.ettus.com > > > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > > > > > > _______________________________________________ > > USRP-users mailing list > > USRP-users@lists.ettus.com > > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com > > > > > > > > -- > > -- > > Sumit kumar > > Doctoral Student, UPMC > > Eurecom, BIOT > > France > > > > -- -- Sumit kumar Doctoral Student, UPMC Eurecom, BIOT France