https://bitwizard.nl/wiki/index.php?action=history&feed=atom&title=Rtc 2026-04-05T19:03:20Z Revision history for this page on the wiki MediaWiki 1.35.6 https://bitwizard.nl/wiki/index.php?title=Rtc&diff=4348&oldid=prev 2018-06-01T11:15:08Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 11:15, 1 June 2018</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 1:</td> <td colspan="2" class="diff-lineno">Line 1:</td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>= Adding the driver =</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>== new version ==</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>Go into raspi-config and enable i2c. </div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>Then add:</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> dtoverlay=i2c-rtc,mcp7941x</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>to your /boot/config.txt</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>== old version ==</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>For historic reasons the old version is still here. Unless you have an old distribution it is recommended you do it the modern way as documented above. </div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div>First, the i2c-bcm2708 i2c driver needs to be loaded. As far as I know, in the first few months of the raspberry pi being available, the module was blacklisted and didn't load automatically. Nowadays "raspi-config" will already give you the option to enable the driver. </div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div>First, the i2c-bcm2708 i2c driver needs to be loaded. As far as I know, in the first few months of the raspberry pi being available, the module was blacklisted and didn't load automatically. Nowadays "raspi-config" will already give you the option to enable the driver. </div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-lineno">Line 12:</td> <td colspan="2" class="diff-lineno">Line 28:</td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device # For rev1 RPi</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device # For rev1 RPi</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device # For rev2 RPi</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device # For rev2 RPi</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>== Using the clock ==</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div>To write the system time to the RTC (you might need to run this command twice, when you use the RTC for the first time):</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div>To write the system time to the RTC (you might need to run this command twice, when you use the RTC for the first time):</div></td> </tr> </table>

Rew https://bitwizard.nl/wiki/index.php?title=Rtc&diff=4081&oldid=prev 2016-08-25T06:02:28Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 06:02, 25 August 2016</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 22:</td> <td colspan="2" class="diff-lineno">Line 22:</td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> hwclock -s</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> hwclock -s</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div>To automatically do this on startup, add the following lines to /etc<del class="diffchange diffchange-inline">/rc.d</del>/rc.local</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>To automatically do this on startup, add the following lines to /etc/rc.local</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c-dev</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c-dev</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c:mcp7941x</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c:mcp7941x</div></td> </tr> <!-- diff cache key wikidb:diff:wikidiff2:1.12:old-3028:rev-4081:1.13.0 --> </table>

Rew https://bitwizard.nl/wiki/index.php?title=Rtc&diff=3028&oldid=prev 2015-01-11T09:31:50Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 09:31, 11 January 2015</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 1:</td> <td colspan="2" class="diff-lineno">Line 1:</td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div>First, the i2c-bcm2708 i2c driver needs to be loaded. As far as I know, in the first few months of the raspberry pi being available, the module was blacklisted and didn't load automatically<del class="diffchange diffchange-inline">,</del> <del class="diffchange diffchange-inline">but</del> <del class="diffchange diffchange-inline">nowadays</del> <del class="diffchange diffchange-inline">the</del> <del class="diffchange diffchange-inline">module</del> <del class="diffchange diffchange-inline">is</del> <del class="diffchange diffchange-inline">loaded</del> <del class="diffchange diffchange-inline">by</del> <del class="diffchange diffchange-inline">default.</del> <del class="diffchange diffchange-inline">If</del> <del class="diffchange diffchange-inline">it</del> <del class="diffchange diffchange-inline">isn't</del> <del class="diffchange diffchange-inline">on your system:</del> </div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>First, the i2c-bcm2708 i2c driver needs to be loaded. As far as I know, in the first few months of the raspberry pi being available, the module was blacklisted and didn't load automatically<ins class="diffchange diffchange-inline">.</ins> <ins class="diffchange diffchange-inline">Nowadays</ins> <ins class="diffchange diffchange-inline">"raspi-config"</ins> <ins class="diffchange diffchange-inline">will</ins> <ins class="diffchange diffchange-inline">already</ins> <ins class="diffchange diffchange-inline">give</ins> <ins class="diffchange diffchange-inline">you</ins> <ins class="diffchange diffchange-inline">the</ins> <ins class="diffchange diffchange-inline">option</ins> <ins class="diffchange diffchange-inline">to</ins> <ins class="diffchange diffchange-inline">enable</ins> <ins class="diffchange diffchange-inline">the</ins> <ins class="diffchange diffchange-inline">driver.</ins> </div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>What "raspi-config" does (but you can also do by hand) is remove the drivers from /etc/modprobe.d/raspi-blacklist.conf . </div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>If the driver isn't loaded on your system start with: </div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> sudo modprobe i2c-bcm2708</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> sudo modprobe i2c-bcm2708</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div><del class="diffchange diffchange-inline">Load</del> the I2C and RTC drivers as root:</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div><ins class="diffchange diffchange-inline">Then load</ins> the I2C and RTC drivers as root:</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> sudo -s</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> sudo -s</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c-dev</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c-dev</div></td> </tr> <!-- diff cache key wikidb:diff:wikidiff2:1.12:old-3027:rev-3028:1.13.0 --> </table>

Rew https://bitwizard.nl/wiki/index.php?title=Rtc&diff=3027&oldid=prev 2015-01-09T09:13:08Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 09:13, 9 January 2015</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 1:</td> <td colspan="2" class="diff-lineno">Line 1:</td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>First, the i2c-bcm2708 i2c driver needs to be loaded. As far as I know, in the first few months of the raspberry pi being available, the module was blacklisted and didn't load automatically, but nowadays the module is loaded by default. If it isn't on your system: </div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> sudo modprobe i2c-bcm2708</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div>Load the I2C and RTC drivers as root:</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div>Load the I2C and RTC drivers as root:</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> sudo -s</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> sudo -s</div></td> </tr> <!-- diff cache key wikidb:diff:wikidiff2:1.12:old-2672:rev-3027:1.13.0 --> </table>

Rew https://bitwizard.nl/wiki/index.php?title=Rtc&diff=2672&oldid=prev 2013-10-07T08:17:45Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 08:17, 7 October 2013</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 18:</td> <td colspan="2" class="diff-lineno">Line 18:</td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c-dev</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c-dev</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c:mcp7941x</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c:mcp7941x</div></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device <del class="diffchange diffchange-inline">//</del> For rev1 RPi</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device <ins class="diffchange diffchange-inline">#</ins> For rev1 RPi</div></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device <del class="diffchange diffchange-inline">//</del> For rev2 RPi</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device <ins class="diffchange diffchange-inline">#</ins> For rev2 RPi</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> hwclock -s</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> hwclock -s</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> </table>

Rew https://bitwizard.nl/wiki/index.php?title=Rtc&diff=2671&oldid=prev 2013-10-07T08:17:17Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 08:17, 7 October 2013</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 1:</td> <td colspan="2" class="diff-lineno">Line 1:</td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div>Load the I2C and RTC drivers as root:</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div>Load the I2C and RTC drivers as root:</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> sudo -s</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c-dev</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c-dev</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c:mcp7941x</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c:mcp7941x</div></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device <del class="diffchange diffchange-inline">//</del> For rev1 RPi</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device <ins class="diffchange diffchange-inline">#</ins> For rev1 RPi</div></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device <del class="diffchange diffchange-inline">//</del> For rev2 RPi</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device <ins class="diffchange diffchange-inline">#</ins> For rev2 RPi</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div>To write the system time to the RTC (you might need to run this command twice, when you use the RTC for the first time):</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div>To write the system time to the RTC (you might need to run this command twice, when you use the RTC for the first time):</div></td> </tr> <!-- diff cache key wikidb:diff:wikidiff2:1.12:old-2532:rev-2671:1.13.0 --> </table>

Rew https://bitwizard.nl/wiki/index.php?title=Rtc&diff=2532&oldid=prev 2013-04-10T13:37:42Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 13:37, 10 April 2013</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 2:</td> <td colspan="2" class="diff-lineno">Line 2:</td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c-dev</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c-dev</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c:mcp7941x</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c:mcp7941x</div></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device<ins class="diffchange diffchange-inline"> // For rev1 RPi</ins></div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device // For rev2 RPi</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div>To write the system time to the RTC (you might need to run this command twice, when you use the RTC for the first time):</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div>To write the system time to the RTC (you might need to run this command twice, when you use the RTC for the first time):</div></td> </tr> <tr> <td colspan="2" class="diff-lineno">Line 16:</td> <td colspan="2" class="diff-lineno">Line 17:</td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c-dev</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c-dev</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> modprobe i2c:mcp7941x</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> modprobe i2c:mcp7941x</div></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td class="diff-deletedline diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device</div></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device<ins class="diffchange diffchange-inline"> // For rev1 RPi</ins></div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-1/device/new_device // For rev2 RPi</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> hwclock -s</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> hwclock -s</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><br /></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><br /></td> </tr> <!-- diff cache key wikidb:diff:wikidiff2:1.12:old-2528:rev-2532:1.13.0 --> </table>

Tom https://bitwizard.nl/wiki/index.php?title=Rtc&diff=2528&oldid=prev 2013-03-27T15:37:20Z

<p></p> <table class="diff diff-contentalign-left diff-editfont-monospace" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:37, 27 March 2013</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 18:</td> <td colspan="2" class="diff-lineno">Line 18:</td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device</div></td> </tr> <tr> <td class="diff-marker"></td> <td class="diff-context diff-side-deleted"><div> hwclock -s</div></td> <td class="diff-marker"></td> <td class="diff-context diff-side-added"><div> hwclock -s</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td class="diff-addedline diff-side-added"><div>Source: http://www.element14.com/community/message/63885</div></td> </tr> <!-- diff cache key wikidb:diff:wikidiff2:1.12:old-2527:rev-2528:1.13.0 --> </table>

Tom https://bitwizard.nl/wiki/index.php?title=Rtc&diff=2527&oldid=prev 2013-03-27T15:36:08Z

<p>Created page with &quot;Load the I2C and RTC drivers as root: modprobe i2c-dev modprobe i2c:mcp7941x echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device To write the system time to th...&quot;</p> <p><b>New page</b></p><div>Load the I2C and RTC drivers as root:<br /> modprobe i2c-dev<br /> modprobe i2c:mcp7941x<br /> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device<br /> <br /> To write the system time to the RTC (you might need to run this command twice, when you use the RTC for the first time):<br /> hwclock -w<br /> <br /> Read out the RTC, and print the date and time to your console:<br /> hwclock<br /> <br /> Read out the RTC, and adjust system time:<br /> hwclock -s<br /> <br /> To automatically do this on startup, add the following lines to /etc/rc.d/rc.local<br /> modprobe i2c-dev<br /> modprobe i2c:mcp7941x<br /> echo mcp7941x 0x6f &gt; /sys/class/i2c-dev/i2c-0/device/new_device<br /> hwclock -s</div>

Tom