As far as I can tell from the pins pdf (in the video) the address of gpio60 is 0x878 where 0x870 is gpio30. So if you echo 30 > export and check the direction there it should be out.
But you don't need to use the DTS unless you have to change from the default mode of the pin (for instance pull-op/down resistors) 2014-12-09 8:21 GMT+01:00 Hemant Kapoor <[email protected]>: > Thanks Jan and Dacobi for your valuable comments. > > There is one small confusion. I declared the pin to be an output pin in my > device tree overlay: > > 0x870 0x07 /* output mode | MODE7, see Pin_Configuration.pdf in BBB > */ > > but after exporting pin as you guys mentioned and looking at the direction, > I get it as 'in' > > root@beaglebone:/sys/class/gpio/gpio60# cat direction > in > > The below steps described by Jan could be done without the use of device > overlay > > > > cd /sys/class/gpio > cd gpio60 > echo 60 > export > echo out > direction > > > echo 1 > value > > So why do we need device overlay :( > > Please help me get rid of this confusion. It is driving me mad.... > > HK! > > > > > On Tuesday, 9 December 2014 01:42:08 UTC, Dacobi wrote: >> >> You need to do >> >> echo 60 > export >> >> Before >> >> cd gpio60 >> >> On Dec 9, 2014 2:32 AM, <[email protected]> wrote: >>> >>> A good tutorial here: >>> >>> http://derekmolloy.ie/gpios-on-the-beaglebone-black-using-device-tree-overlays/ >>> simple example: >>> cd /sys/class/gpio >>> cd gpio60 >>> echo 60 > export >>> echo out > direction >>> echo 1 > value >>> >>> good luck >>> Jan >>> >>> >>> >>> >>> >>> >>> On Tuesday, December 9, 2014 1:41:10 AM UTC+11, Hemant Kapoor wrote: >>>> >>>> Hello All, >>>> >>>> I am a newbie to Linux and trying to figure out how device tree overlay >>>> works... >>>> >>>> So after googling for many days, I came up with below device tree: >>>> >>>> /dts-v1/; >>>> /plugin/; >>>> >>>> / { >>>> compatible = "ti,beaglebone", "ti,beaglebone-black"; >>>> >>>> /* identification */ >>>> part-number = "MY-LED"; >>>> version = "00A0"; >>>> >>>> /* state the resources this cape uses */ >>>> exclusive-use = >>>> /* the pin header uses */ >>>> "P9.12", /* GPIO*/ >>>> /* the hardware ip uses */ >>>> "gpio0"; >>>> >>>> fragment@0 { >>>> target = <&am33xx_pinmux>; >>>> __overlay__ { >>>> bb_mygpio_pins: pinmux_bb_mygpio_pins { >>>> pinctrl-single,pins = < >>>> 0x870 0x07 /* >>>> output mode | MODE7, see Pin_Configuration.pdf in BBB */ >>>> >; >>>> }; >>>> }; >>>> }; >>>> >>>> fragment@1 { >>>> target = <&ocp>; /* not sure why it is not gpio0 >>>> */ >>>> __overlay__ { >>>> status = "okay"; >>>> pinctrl-names = "default"; >>>> pinctrl-0 = <&bb_mygpio_pins>; >>>> }; >>>> }; >>>> }; >>>> >>>> >>>> I was able to "build" the dtc and generated MY-LED-00A0.dtbo >>>> >>>> I then copied the MY-LED-00A0.dtbo to /lib/firmware >>>> >>>> Then i echoed it to slots: >>>> echo MY-LED > $SLOTS >>>> >>>> and cat $SLOTS gives me below result: >>>> >>>> root@beaglebone:/lib/firmware# cat $SLOTS >>>> 0: 54:PF--- >>>> 1: 55:PF--- >>>> 2: 56:PF--- >>>> 3: 57:PF--- >>>> 4: ff:P-O-L Bone-LT-eMMC-2G,00A0,Texas Instrument,BB-BONE-EMMC-2G >>>> 5: ff:P-O-- Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI >>>> 6: ff:P-O-- Bone-Black-HDMIN,00A0,Texas Instrument,BB-BONELT-HDMIN >>>> 9: ff:P-O-L Override Board Name,00A0,Override Manuf,MY-LED >>>> >>>> By looks of this, MY_LED seems to be loaded... >>>> >>>> >>>> The main confusion is how can I use MY-LED? >>>> Where are the files for MY-LED present? >>>> >>>> Any help or guidance is much appreciated. >>>> >>> -- >>> 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 [email protected]. >>> 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 [email protected]. > For more options, visit https://groups.google.com/d/optout. -- "Capitalism is the extraordinary belief that the nastiest of men for the nastiest of motives will somehow work for the benefit of all." - Unknown -- 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 [email protected]. For more options, visit https://groups.google.com/d/optout.
