config-pin P9_26 gpio ERROR: open() for /sys/devices/platform/ocp/ocp:P9_26_pinmux/state failed, No such file or directory
write "in" to /sys/class/gpio/gpio14/direction (for input) write "out" to /sys/class/gpio/gpio14/direction (for output) ... Did you mean gpio15 (not gpio14)? gpio15 ... UART1_TXD I will try UART4_RXD (P9_11 - gpio30) and UART4_TXD (P9_13 - gpio31). Dátum: streda 30. júna 2021, čas: 17:21:06 UTC+2, odosielateľ: hel...@deepsoft.com > At Wed, 30 Jun 2021 07:03:38 -0700 (PDT) beagl...@googlegroups.com wrote: > > > > > I tried to use write operation on /sys/class/gpio/gpio14 (gpio15)/value, > > but nothing happens (from > > https://github.com/RobertPHeller/JAVALinuxGPIO/blob/main/LinuxGPIO.java > ) > > I figured out that PrintStream doesn't throw exceptions so I tried to > use > > FileOutputStream. > > Then I got exception: > > > > java.io.IOException: Operation not permitted > > at java.io.FileOutputStream.write(Native Method) > > at java.io.FileOutputStream.write(FileOutputStream.java:290) > > > > Read operation via FileInputStream is ok. > > > > I run my java application with "sudo". > > > > gpio14 ... P9_24 (UART1_TXD) > > gpio15 ... P9_26 (UART1_RXD) > > Right? > > First of all you need to configure the pins: > > config-pin P9_24 gpio > config-pin P9_26 gpio > ("config-pin -l P9_24" list the possible options, "config-pin -q P9_24" > displays the current settings. There is an extended versin of config-pin > under /opt/source/bb.org-overlays/tools/beaglebone-universal-io/) > > You then need to "export" the GPIO pins: > > write "14" to /sys/class/gpio/export > write "15" to /sys/class/gpio/export > > You also need to configure the direction: > > write "in" to /sys/class/gpio/gpio14/direction (for input) > write "out" to /sys/class/gpio/gpio14/direction (for output) > > (My GPIO class does that in the constructor) > > To avoid sudo, you put yourself into the gpio group: > > sudo usermod -a -G gpio $USER > > then logout and log back in. > > > > > > > Dátum: utorok 29. júna 2021, Ä as: 16:42:45 UTC+2, odosielateľ: > Dennis Bieber > > > > > On Tue, 29 Jun 2021 07:02:06 -0700 (PDT), in > > > gmane.comp.hardware.beagleboard.user Radovan Chovan > > > <rado991-re5jqee...@public.gmane.org> wrote: > > > > > > >Thanks for all your comments. > > > > > > > >Is there any mapping between /sys/class/gpio and schematic diagram of > > > >Beaglebone Black board? > > > > > > > Does > > > https://vadl.github.io/beagleboneblack/2016/07/29/setting-up-bbb-gpio > > > provide any help. > > > > > > >I want to use pin P9_24 (UART1_TXD) and P9_26 (UART1_RXD). > > > >https://beagleboard.org/static/beaglebone/BEAGLEBONE_SCHEM_A3.pdf > (page > > > >11/11) > > > > > > > P9_24 equates to GPIO15, but in raw pin numbering appears to be 97. As > > > I recall, there are 32 GPIOs per "CHIP", so that might be the 4th CHIP > > > (counting from 0), and the second GPIO (again, counting from 0) > > > > > > >>> divmod(97, 32) > > > (3, 1) > > > > > > P9_26 -> GPIO14, raw 96... > > > > > > >>> divmod(96, 32) > > > (3, 0) > > > >>> > > > > > > HOWEVER, > > > debian@beaglebone:~$ gpioinfo > > > gpiochip0 - 32 lines: > > > line 0: "MDIO_DATA" unused input active-high > > > <SNIP> > > > line 12: "UART1_CTSN" "P9_20" input active-high [used] > > > line 13: "UART1_RTSN" "P9_19" input active-high [used] > > > line 14: "UART1_RXD" "P9_26" input active-high [used] > > > line 15: "UART1_TXD" "P9_24" input active-high [used] > > > line 16: "GMII1_TXD3" unused input active-high > > > > > > indicates that it is CHIP0, and the "line" 14/15 map to the GPIOxx (so > for, > > > say, GPIO45 it becomes chip 1, line 13) > > > > > > The gpioinfo command is provided by installing the gpiod package. > > > > > > > > > debian@beaglebone:~$ > > > /opt/source/bb.org-overlays/tools/beaglebone-universal-io/config-pin -i > > > p9_26 > > > Pin name: P9_26 > > > Function if no cape loaded: gpio > > > Function if cape loaded: default gpio gpio_pu gpio_pd gpio_input uart > can > > > i2c pru_uart pruin > > > Function information: gpio0_14 default gpio0_14 gpio0_14 gpio0_14 > gpio0_14 > > > uart1_rxd dcan1_tx i2c1_sda pru_uart pru1_in16 > > > Kernel GPIO id: 14 > > > PRU GPIO id: 46 > > > debian@beaglebone:~$ > > > /opt/source/bb.org-overlays/tools/beaglebone-universal-io/config-pin -i > > > p9_24 > > > Pin name: P9_24 > > > Function if no cape loaded: gpio > > > Function if cape loaded: default gpio gpio_pu gpio_pd gpio_input uart > can > > > i2c pru_uart pruin > > > Function information: gpio0_15 default gpio0_15 gpio0_15 gpio0_15 > gpio0_15 > > > uart1_txd dcan1_rx i2c1_scl pru_uart pru0_in16 > > > Kernel GPIO id: 15 > > > PRU GPIO id: 47 > > > debian@beaglebone:~$ > > > > > > > > > (Unfortunately, that script doesn't tell one what "default" mode IS > for the > > > pin, but does have more capability than the compiled config-pin that > > > replaces it) > > > > > > > > > -- > > > Dennis L Bieber > > > > > > > > > > -- > Robert Heller -- Cell: 413-658-7953 <(413)%20658-7953> GV: 978-633-5364 > <(978)%20633-5364> > Deepwoods Software -- Custom Software Services > http://www.deepsoft.com/ -- Linux Administration Services > hel...@deepsoft.com -- Webhosting Services > > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. 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