Hi, i´m using the latest Debian Image an I´m trying to set an external RTC as a hardwareclock for my BBB. I have a different RTC module (PCF8563) but basicly I stick to the following manual: https://learn.adafruit.com/adding-a-real-time-clock-to-beaglebone-black/set-rtc-time
What I dont understand here is the following: The author sets the ds1307 as a new i2c device with the command: echo ds1307 0x68 > /sys/class/i2c-adapter/i2c-1/new_device In the next step he can already access the new rtc1 device. hwclock -r -f /dev/rtc1 Why is that? How does the system know that the new i2c device connected is a RTC and how to access it. Is there a preinstalled driver for DS1307? According to the manual I did the following: echo pcf8563 0x51 > /sys/class/i2c-adapter/i2c-2/new_device My PCF8563 is getting recognized as rtc1 (not sure why - I havent installed any drivers?) When I try to access hwclock -r -f /dev/rtc1 I just get hwclock: ioctl(RTC_RD_TIME) to /dev/rtc1 to read the time failed: Invalid argument Does anyone have some hints on that? Cheers. -- 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/9645489d-9a24-4888-b124-e3eeac3f0811%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
