RasClock v5.0 is a highly accurate real-time clock that plugs directly into the Raspberry Pi and includes a battery backup. The module is installed directly into the GPIO header pins with no wiring or soldering. It uses the 3.3V, GND SDA and SCL pins. The module stays within the outline of the Raspberry Pi and sits lower than video output so can be easilly installed within most cases.
RasClock uses one of the following chips:
RasClock features:
Why do I need a Real Time Clock for my Raspberry Pi?
Complete installation and set up instructions can be found at http://afterthoughtsoftware.com/products/rasclock
Additional tutorial can be found at https://www.modmypi.com/blog/installing-the-rasclock-raspberry-pi-real-time-clock
Set up is easy, simply follow the guide Outlined in the ModMyPi Raspberry Pi Tutorial Here!
How to check what version of hardware and software running on your Raspberry Pi:
pi@raspberrypi:/$ sudo bash
pi@raspberrypi:/# cat /proc/cpuinfo
Processor : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS : 697.95
Features : swp half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0
CPU part : 0xb76
CPU revision : 7
Hardware : BCM2708
Revision : 0003
Serial : 00000000c0ae10d9
root@raspberrypi:/# cat /etc/debian_version
7.1
root@raspberrypi:/# uname -or
3.6.11+ GNU/Linux
How to configure RTC module and remove fake-hwclock (when using wheezy 3.6.11):
sudo bash
apt-get remove fake-hwclock
rm /etc/cron.hourly/fake-hwclock
update-rc.d -f fake-hwclock remove
rm /etc/init.d/fake-hwclock
rpi-update
wget http://afterthoughtsoftware.com/files/linux-image-3.6.11-atsw-rtc_1.0_armhf.de
dpkg -i linux-image-3.6.11-atsw-rtc_1.0_armhf.deb
cp /boot/vmlinuz-3.6.11-atsw-rtc+ /boot/kernel.img
echo "i2c-bcm2708" >> /etc/modules
echo "rtc-pcf2127a" >> /etc/modules
Add the following to /etc/rc.local before "exit 0":
# Referring to
# http://www.raspberrypi-spy.co....
# to get the RasPi board version:
REV=$(cat /proc/cpuinfo|grep Revision)
# Extract revision
REV=${REV##*: }
# Make it readable as hex
REV=0x$REV
# Convert hex to dec
REV=$((REV))
if [ $REV -lt 4 ]
then
echo pcf2127a 0x51 > /sys/class/i2c-adapter/i2c-0/new_device
echo setting rtc to i2c-0
else
echo pcf2127a 0x51 > /sys/class/i2c-adapter/i2c-1/new_device
echo setting rtc to i2c-1
fi
( sleep 2; hwclock -s ) &
Then reboot:
sync
reboot
Console should show similar to:
[ 32.897890] rtc-pcf2127a 0-0051: chip found
[ 32.899695] rtc-pcf2127a 0-0051: rtc core: registered rtc-pcf2127a as rtc0
[ 32.899757] i2c i2c-0: new_device: Instantiated device pcf2127a at 0x51
Then later nearer the login prompt:
Board revision: X
setting rtc to i2c-X
Log back in and verify date is correct:
date
Set hardware clock to current system time:
sudo hwclock -w
Verify hardware clock is set correctly:
sudo hwclock -r
Showing reviews 1-2 of 7 | Next
Posted by Unknown on 22nd Dec 2016
I had no issues with the RasClock. It fits in the standard case nicely with plenty of clearance.
It connects to the GPIO header so you cannot use it with other PI caps.
Posted by Unknown on 26th Oct 2015
RasClock works as described! I am using it with Falcon Player so the system knows when to fire-off events and, so far in my testing, it works as it should.
My only gripe is that since the chip/battery are mounted on the bottom, they are sort of clock to the heatsink of one of the rPi chips.
Showing reviews 1-2 of 7 | Next