On Thu, Aug 23, 2018 at 2:33 PM <[email protected]> wrote: > > Hello, > My goal is to make an ultra-precise clock on the beaglebone black by using > the 1 pps signal from my adafruit GPS. I have been readying about the device > overlays / capes but there seems to be a lot of outdated information out > there that is very confusing. > > My 1 pps is connected to P9_12 > GPS Rx: P9_24 > GPS Tx: P9_26 > > I found the following DTS file: > https://github.com/ddrown/pps-gmtimer/blob/master/DD-GPS-00A0.dts > > I then edited this file, and replaced the pins with my pins as listed above. > After compiling the file, I get the following warning: > > root@AD1:/lib/firmware# dtc -O dtb -o /lib/firmware/DD-GPS-00A0.dtbo -b 0-@ > DD-GPS-00A0.dts > /lib/firmware/DD-GPS-00A0.dtbo: Warning (unit_address_vs_reg): Node > /fragment@0 has a unit name, but no reg property > /lib/firmware/DD-GPS-00A0.dtbo: Warning (unit_address_vs_reg): Node > /fragment@1 has a unit name, but no reg property > /lib/firmware/DD-GPS-00A0.dtbo: Warning (unit_address_vs_reg): Node > /fragment@2 has a unit name, but no reg property > > Then, I edited my /boot/uEnv.txt and pointed: > uboot_overlay_addr0=/lib/firmware/DD-GPS-00A0.dtbo > > I next rebooted, and expected to see something in dmesg about the 1pps > signal, but I didn't. I do see the following: > > root@AWD1:/lib/firmware# dmesg |grep pps > [ 0.725865] pps_core: LinuxPPS API ver. 1 registered > [ 0.725871] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo > Giometti <[email protected]> > > Any thoughts as to why I am not seeing a /dev/pps0 device?
Use this overlay as an example: https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/PB-UART4-GNSS-5-CLICK.dts https://download.mikroe.com/documents/add-on-boards/click/gnss-5/gnss-5-click-schematic-v101.pdf Regards, -- Robert Nelson https://rcn-ee.com/ -- 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/CAOCHtYj%2Bi6-7M3TTmTY6GGwwY3JO6bUPzhhs_hnEUDa6Vfn%2B0A%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
