From: halfbrain <adrian.mitev...@gmail.com> Reply-To: "beagleboard@googlegroups.com" <beagleboard@googlegroups.com> Date: Monday, September 1, 2014 at 8:23 AM To: "beagleboard@googlegroups.com" <beagleboard@googlegroups.com> Subject: Re: [beagleboard] Can "allocated pins" on BBB be used as GPIOs ?
> I'm using Derek Molloys device Tree overlays and I'm running debian... I can't > find the folder on my bbb . > > But I found the "am335x-bone-common.dtsi > <https://github.com/derekmolloy/boneDeviceTree/blob/master/DTSource3.8.13/am33 > 5x-bone-common.dtsi> " in > https://github.com/derekmolloy/boneDeviceTree/tree/master/DTSource3.8.13 which > I have on my bbb. I've commented out the section you mentioned but nothing > changes. Without using or declaring the I2c2 pins in my Device Tree Overlay > I'm able to use all unallocated pins as GPIO Inputs as I declared them in my > Device Tree Overlay. > > Did i change the wrong am335x-bone-common.dtsi > <https://github.com/derekmolloy/boneDeviceTree/blob/master/DTSource3.8.13/am33 > 5x-bone-common.dtsi> .? Is there another one elsewhere on the debian > distribution or do i have to copy the changed file into a specific folder? You need to follow: http://eewiki.net/display/linuxonarm/BeagleBone+Black#BeagleBoneBlack-LinuxK ernel After the kernel has built, you will see a KERNEL folder which includes the complete Linux Kernel. In that folder, go to /arch/arm/boot/dts and edit the am335x-bone-common.dtsi file. After that, return to the bb-kernel folder and run tools/rebuild.sh script. The build results will be in the deploy folder which you need to copy to your sdcard/³nfs folder². Regards, John > > > Am Sonntag, 31. August 2014 20:59:21 UTC+2 schrieb john3909: >> >> From: halfbrain <adrian....@gmail.com <javascript:> > >> Reply-To: "beagl...@googlegroups.com <javascript:> " >> <beagl...@googlegroups.com <javascript:> > >> Date: Sunday, August 31, 2014 at 2:30 AM >> To: "beagl...@googlegroups.com <javascript:> " <beagl...@googlegroups.com >> <javascript:> > >> Subject: Re: [beagleboard] Can "allocated pins" on BBB be used as GPIOs ? >> >>> how do u use the i2c2 pins? it doesn't work on my bbb if i only change the >>> pinmode to mode 7 in my device tree. have u done additional changes or >>> something like that elsewhere? >> If you look at /arch/arm/boot/dts/am335x-bone-common.dtsi you will see the >> i2c2 definition: >> >> &i2c2 { >> status = "okay"; >> pinctrl-names = "default"; >> pinctrl-0 = <&i2c2_pins>; >> clock-frequency = <100000>; >> cape_eeprom0: cape_eeprom0@54 { >> compatible = "at,24c256"; >> reg = <0x54>; >> }; >> cape_eeprom1: cape_eeprom1@55 { >> compatible = "at,24c256"; >> reg = <0x55>; >> }; >> cape_eeprom2: cape_eeprom2@56 { >> compatible = "at,24c256"; >> reg = <0x56>; >> }; >> cape_eeprom3: cape_eeprom3@57 { >> compatible = "at,24c256"; >> reg = <0x57>; >> }; >> }; >> The line ³pinctrl-0 = <&i2c2_pins>;² refers to the i2cs_pins label in the >> pinmux section: >> >> i2c2_pins: pinmux_i2c2_pins { >> pinctrl-single,pins = < >> 0x178 0x73 /* uart1_ctsn.i2c2_sda, SLEWCTRL_SLOW | INPUT_PULLUP | MODE3 */ >> 0x17c 0x73 /* uart1_rtsn.i2c2_scl, SLEWCTRL_SLOW | INPUT_PULLUP | MODE3 */ >>> >; >> }; >> >> So, as you can see, i2c2 is used to identify the capes plugged into the BBB. >> If you don¹t need this feature, simply remove or comment out this section and >> then change the i2c2 pins to gpio pins. >> >> Regards, >> John >>> >>> Am Montag, 19. Mai 2014 12:20:03 UTC+2 schrieb Dhruv Vyas: >>>> Thanks John. Got it cleared. :) >>>> >>>> On Monday, May 19, 2014 1:49:16 AM UTC+5:30, john3909 wrote: >>>>> >>>>> From: Dhruv Vyas <dhruv....@gmail.com> >>>>> Reply-To: <beagl...@googlegroups.com> >>>>> Date: Sunday, May 18, 2014 at 2:42 AM >>>>> To: <beagl...@googlegroups.com> >>>>> Subject: [beagleboard] Can "allocated pins" on BBB be used as GPIOs ? >>>>> >>>>>> Hello, >>>>>> >>>>>> I recently started working on my BBB A6A. I went through necessary >>>>>> getting started guides and it works like a charm. Now as a part of my >>>>>> project, I need to use some of the GPIOs on P8/P9 header. While googling >>>>>> how to use them as a GPIO, and how to set pinmux and etc, I went through >>>>>> this guide. >>>>>> http://derekmolloy.ie/gpios-on-the-beaglebone-black-using-device-tree-ove >>>>>> rlays/ and he explained everything very clearly. >>>>>> >>>>>> Now my question is : is there any way i can use allocated pins as GPIOs >>>>>> other than available pins ? If yes, how ? If no, why ? >>>>>> >>>>>> For example, P9_19 and P9_20 are Allocated to (Group: pinmux_i2c2_pins) >>>>>> and hence it can not be used as GPIOs ? >>>>> If pins are also connected to circuitry on the board that cannot be >>>>> disabled then you cannot use those pins for GPIO. For example, pins used >>>>> for the eMMC can be used for GPIO as long as eMMC is disabled. Same for >>>>> LCD pins, but then you cannot use LCD or HDMI. I2C2 isn¹t connected to >>>>> other circuity on the board so you can use it for GPIO. >>>>> >>>>> Regards, >>>>> John >>>>>> >>>>>> >>>>>> Thanks. >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> 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...@googlegroups.com. >>>>>> For more options, visit https://groups.google.com/d/optout. >>> >>> -- >>> 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...@googlegroups.com <javascript:> . >>> For more options, visit https://groups.google.com/d/optout. >> >> -- >> 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. >> For more options, visit https://groups.google.com/d/optout. >> -- 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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