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Forum PiFace Shim RTC not recognised on a RPi B+
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Related

PiFace Shim RTC not recognised on a RPi B+

Former Member
Former Member over 10 years ago

PiFace Shim RTC not recognised on a RPi B+

 

New stock Raspberry Pi B+, new stock PiFace Shim RTC, fresh battery, all updates applied

 

Here's the error messages

 

pi@raspberrypi ~ $ hwclock

hwclock: Cannot access the Hardware Clock via any known method.

hwclock: Use the --debug option to see the details of our search for an access method.

 

pi@raspberrypi ~ $ sudo hwclock

hwclock: Cannot access the Hardware Clock via any known method.

hwclock: Use the --debug option to see the details of our search for an access method.

 

pi@raspberrypi ~ $ sudo hwclock -s

hwclock: Cannot access the Hardware Clock via any known method.

hwclock: Use the --debug option to see the details of our search for an access method.

pi@raspberrypi ~ $ sudo hwclock --debug

hwclock from util-linux 2.20.1

hwclock: Open of /dev/rtc failed: No such file or directory

No usable clock interface found.

hwclock: Cannot access the Hardware Clock via any known method.

 

Cheers

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Top Replies

  • Former Member
    Former Member over 10 years ago in reply to Former Member +1
    Hi, seems to work now: sudo hwclock -r su 15. helmikuuta 2015 23.54.22 -0.035001 seconds In my case Raspberry's i2c did not work properly and there seems to be some problem in installation script, too…
  • Former Member
    Former Member over 10 years ago in reply to Former Member +1
    Jukka, I want to thank you very much for this splendid piece of work which taught me a lot. Prof. of Physics, CERN collaborator for over 50 years, I have seen very few such things. Jacques Goldberg
  • mconners
    mconners over 9 years ago in reply to mconners +1
    As promised here is my experience setting up a RTC device via I2C on a Ras Pi 2 Enabling RTC on the Raspberry Pi 2 Mike
Parents
  • piknot
    0 piknot over 9 years ago

    New to Pi and Linux so bear with me.  I followed the user manual/guide and: https://www.element14.com/community/message/138941/l/re-piface-shim-rtc-not-recognised-on-a-rpi-b#138941

    Continue to receive:

    hwclock: Cannot access the Hardware Clock via any known method.

    hwclock: Use the --debug option to see the details of our search for an access method.

     

    Tried:

     

    Loading and testing the PiFace Shim RTC module

     

    sudo modprobe i2c:mcp7941x

     

    and then with root rights (= sudo bash)

     

    echo mcp7941x 0x6f > /sys/class/i2c-adapter/i2c-1/new_device

     

    exit (= to quit root rights' shell)

     

     

    but I get:

     

    bash: /sys/class/i2c-adapter/i2c-1/new_device: Permission denied

     

    Thank you

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  • clem57
    0 clem57 over 9 years ago in reply to piknot

    Try:

    sudo echo mcp7941x 0x6f > /sys/class/i2c-adapter/i2c-1/new_device

    Clem

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  • clem57
    0 clem57 over 9 years ago in reply to piknot

    Try:

    sudo echo mcp7941x 0x6f > /sys/class/i2c-adapter/i2c-1/new_device

    Clem

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  • mconners
    0 mconners over 9 years ago in reply to clem57

    Clem Martins wrote:

     

    Try:

    sudo echo mcp7941x 0x6f > /sys/class/i2c-adapter/i2c-1/new_device

    Clem

    I tried that the other day and got a permission denied. I just retried and got a permission denied.

     

    sudo echo mcp7941x 0x6f > /sys/class/i2c-adapter/i2c-1/new_device

    -bash: /sys/class/i2c-adapter/i2c-1/new_device: Permission denied

     

    BTW, I wrote a blog post on enabling a DS 1307 RTC via I2C that I will be publishing after work. I will post a link here.

     

    After seeing a few questions on here about it I had to try it myself to see if there were any gotchas.

     

    Mike

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  • mconners
    0 mconners over 9 years ago in reply to mconners

    As promised here is my experience setting up a RTC device via I2C on a Ras Pi 2

     

    Enabling RTC on the Raspberry Pi 2

     

    Mike

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