Hello BBB Gurus, Summary, having loaded up the device tree overlay, correctly (?) and identifying that the overlay is indeed loaded, the pin configured, and the circuit correct (all according to http://www.bonebrews.com/temperature-monitoring-with-the-ds18b20-on-a-beaglebone-black/ ), my BBB will not detect any of the DS18B20's that I connect (I've tried 5). I've tried a second BBB, with the same result.
I'm after suggestions to troubleshoot this further --as I have basically run aground at this point! Some detail: kernel: 3.8.13-bone70 Device tree overlay: /* * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Modified by Russell Senior from the weather cape's DTS file. * Minor formatting by C W Rose. */ /dts-v1/; /plugin/; / { compatible = "ti,beaglebone", "ti,beaglebone-black"; part-number = "BB-W1"; version = "00A0"; exclusive-use = "P8.11"; fragment@0 { target = <&am33xx_pinmux>; __overlay__ { bb_w1_pins: pinmux_bb_w1_pins { pinctrl-single,pins = <0x34 0x37 /* gpmc_ad13.gpio1_13, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE7 - w1-gpio */ >; }; }; }; fragment@1 { target = <&ocp>; __overlay__ { onewire@0 { compatible = "w1-gpio"; status = "okay"; pinctrl-names = "default"; pinctrl-0 = <&bb_w1_pins>; gpios = <&gpio1 2 0>; }; }; }; }; Relevant output from dmesg: [ 8.697062] bone-capemgr bone_capemgr.9: part_number 'w1', version 'N/A' [ 8.697138] bone-capemgr bone_capemgr.9: slot #7: generic override [ 8.697155] bone-capemgr bone_capemgr.9: bone: Using override eeprom data at slot 7 [ 8.697171] bone-capemgr bone_capemgr.9: slot #7: 'Override Board Name,00A0,Override Manuf,w1' [ 8.697259] bone-capemgr bone_capemgr.9: slot #7: Requesting part number/version based 'w1-00A0.dtbo [ 8.697274] bone-capemgr bone_capemgr.9: slot #7: Requesting firmware 'w1-00A0.dtbo' for board-name 'Override Board Name', version '00A0' [ 8.727950] bone-capemgr bone_capemgr.9: slot #7: dtbo 'w1-00A0.dtbo' loaded; converting to live tree [ 8.728198] bone-capemgr bone_capemgr.9: slot #7: #2 overlays [ 8.757662] bone-capemgr bone_capemgr.9: slot #7: Applied #2 overlays. Slots: root@beaglebone:~# cat /sys/devices/bone_capemgr.9/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-L Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI 7: ff:P-O-L Override Board Name,00A0,Override Manuf,w1 It's not seeing any of the sensors: root@beaglebone:~# ls /sys/bus/w1/devices/w1_bus_master1 driver power subsystem uevent w1_master_add w1_master_attempts w1_master_max_slave_count w1_master_name w1_master_pointer w1_master_pullup w1_master_remove w1_master_search w1_master_slave_count w1_master_slaves w1_master_timeout Voltages across the DQ and ground pin of the DS18B20's is just under 3.3 V, and a bit higher across the power to grnd pin. So pullup appears correct. Could someone suggest some further troubleshooting approaches? Hey, I'll take solutions as well! Thanks for your help. Kind regards Matt -- 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.
