Another problem I'm seeing with your "wiring diagram". You're powering the sensor via 3v3, but you still have the parasitic power resistor in place. It is my understanding if you're wanting to power the DS18B20 from the dataline. In whcih case the resistor would be between Vdd, and DQ pins (pins 2 and 3 ). *HOWEVER* keep in mind that I'm pretty sure you can not power the DS18B20 from the beaglebone's GPIO pins.
Anyway, I just happen to have a DS18B20 in hand at this very moment. So I'll hook up some jumper wires from the P9 headers for ground, 3v3, or 5v, and a data pin to give it a test. I'll even write, or more correctly modify the existing 1-wire dtb i linked to earlier to match your exact needs. As it just so happens I have to get 1-wire working myself. As I'm in the process of designing my own 1-wire slave devices. On Thu, Dec 1, 2016 at 8:47 PM, William Hermans <yyrk...@gmail.com> wrote: > On Thu, Dec 1, 2016 at 10:57 AM, Sebastián Sáez <otra...@gmail.com> wrote: > >> Hi Dennis, >> >> I attach my circuit. It's connected to P9_22 with a pullup 4.7K resistor. >> Now I'm trying with BBGW-blank-debian-8.5-seeed-iot-armhf-2016-06-19-4gb >> >> I try with this module from this tutorial >> <http://mkaczanowski.com/one-wire-ds1820-thermometer-with-beaglebone-black-libmicrohttpd/> >> : >> >> /dts-v1/; >>> /plugin/; >>> >>> / { >>> compatible = "ti,beaglebone", "ti,beaglebone-black"; >>> part-number = "BB-W1"; >>> version = "00A0"; >>> >>> /* state the resources this cape uses */ >>> exclusive-use = >>> /* the pin header uses */ >>> "P9.22", >>> /* the hardware IP uses */ >>> "gpio0_2"; >>> >>> fragment@0 { >>> target = <&am33xx_pinmux>; >>> __overlay__ { >>> dallas_w1_pins: pinmux_dallas_w1_pins { >>> pinctrl-single,pins = < 0x150 0x37 >; >>> }; >>> }; >>> }; >>> >>> fragment@1 { >>> target = <&ocp>; >>> __overlay__ { >>> onewire@0 { >>> compatible = "w1-gpio"; >>> pinctrl-names = "default"; >>> pinctrl-0 = <&dallas_w1_pins>; >>> status = "okay"; >>> >>> gpios = <&gpio1 2 0>; >>> }; >>> }; >>> }; >>> }; >> >> >> I notice that the bone_capemgr from /sys/devices/bone_capemgr.9/slots to >> /sys/devices/platform/bone_capemgr/slots >> >> I can't found the w1 kernel module at /sys/bus/w1/devices/DEVICE_ID >> /w1_slave >> >> >> regards, >> Sebastián >> >> > You device tree file is wrong. First lets look at this compared to your > file: https://github.com/beagleboard/bb.org-overlays/ > blob/master/src/arm/BB-W1-P9.12-00A0.dts#L25-L27 > > exclusive-use = > /* the pin header uses */ > "P9.22", > /* the hardware IP uses */ > "gpio0_2"; > > should be: > > > exclusive-use = > /* the pin header uses */ > "P9.22"; > > > The comment is also wrong, but whatever, it shouldn't hurt anything. > > Second: > > > fragment@1 { > target = <&ocp>; > __overlay__ { > onewire@0 { > compatible = "w1-gpio"; > pinctrl-names = "default"; > pinctrl-0 = <&dallas_w1_pins>; > status = "okay"; > > *gpios = <&gpio1 2 0>;* > }; > > The code in bold is wrong. The gpio bank for this pin is bank0: > > *gpios = <&gpio0 2 0>; *would be the correct assignment. > > Lastly, your overlay "compatible" assignment is wrong for your board. It > should look like this: > > https://github.com/beagleboard/bb.org-overlays/ > blob/master/src/arm/BB-W1-P9.12-00A0.dts#L18 > > > -- 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/CALHSORqOahDP0Od7NeFdN4--%3DE2FHiJnvp2n19R9BSNHao-HKw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
