At Tue, 29 Jun 2021 07:02:06 -0700 (PDT) beagleboard@googlegroups.com wrote:
> > Thanks for all your comments. > > Is there any mapping between /sys/class/gpio and schematic diagram of > Beaglebone Black board? No. /sys/class/gpio just uses the GPIO numbers. The mapping of GPIO N.M is: N*32+M eg GPIO 2.05 is 69 > > 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) If you want to use these pins as UART1, (the default), you can use /dev/ttyS1. Otherwise you should use config-pin to select the mode: For GPIO -- #0.15 for P9_24 and #0.14 for P9_26: config-pin P9_24 gpio config-pin P9_24 gpio_pu config-pin P9_24 gpio_pd config-pin P9_24 gpio_input config-pin P9_26 gpio config-pin P9_26 gpio_pu config-pin P9_26 gpio_pd config-pin P9_26 gpio_input For CAN (can1) config-pin P9_24 can config-pin P9_26 can For I2C (i2c1) config-pin P9_24 i2c config-pin P9_26 i2c > > Dátum: Å¡tvrtok 24. júna 2021, Ä as: 18:11:14 UTC+2, odosielateľ: Dennis > Bieber > > > On Thu, 24 Jun 2021 07:17:59 -0400 (EDT), in > > gmane.comp.hardware.beagleboard.user Robert Heller > > <heller-2/ccJrXdU8tWk0Htik3J/w...@public.gmane.org> wrote: > > > > >At Thu, 24 Jun 2021 03:47:49 -0700 (PDT) beagleboard-/ > > jypxa39uh5...@public.gmane.org wrote: > > > > > >> > > >> I have complex Java application where using GPIO is only part of it. > > > > > >OK, probably the "easiest" (and Linux-only) way to add GPIO access is use > > the > > >sysfs interface. > > > > > At least until the Linux developers remove it... My understanding is > > that sysfs is currently "deprecated", the replacement being libgpiod -- a > > "character" device driver. > > > > Unfortunately, for libgpiod, JAVA probably needs an interface library > > to be created -- quick search finds > > https://github.com/mattjlewis/diozero (though there are some mentions of > > sysfs in the commentary, but perusing > > > > https://github.com/mattjlewis/diozero/blob/main/system-utils-native/src/main/c/com_diozero_internal_provider_builtin_gpio_NativeGpioDevice.c > > appears to be the libgpiod chip devices). > > > > There is also this one https://github.com/sgjava/java-periphery > > > > > > -- > > Dennis L Bieber > > > > > -- Robert Heller -- Cell: 413-658-7953 GV: 978-633-5364 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. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/20210629143630.C4591220CD0%40sharky4.deepsoft.com.