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davidebettio/50-i2c_start.rules

Forked from Lahorde/0_README.md
Created July 12, 2016 12:26
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Initialize an external I2C RTC module on raspberry using udev and systemd
Raw
50-i2c_start.rules
# /etc/udev/rules.d/rtc-i2c.rules
#
#
#I2C hardware device driver
ACTION=="add", KERNEL=="i2c_bcm2708", SUBSYSTEM=="module", TAG+="systemd"
Raw
60-rtc-i2c.rules
# /etc/udev/rules.d/rtc-i2c.rules
#
#
ACTION=="add", SUBSYSTEM=="rtc", ATTRS{hctosys}=="0", RUN+="/usr/bin/hwclock -s --utc"
Raw
i2c_rtc.service
# /etc/systemd/system/i2c_rtc.service
[Unit]
Description=Initialize i2c hardware RTC device driver
DefaultDependencies=no
Requires=sys-module-i2c_bcm2708.device
After=sys-module-i2c_bcm2708.device
Conflicts=shutdown.target
[Service]
Type=oneshot
RemainAfterExit=yes
EnvironmentFile=/etc/conf.d/rtc-i2c
ExecStart=/bin/sh -c "echo ${CHIP} ${ADDRESS} > /sys/class/i2c-adapter/i2c-${BUS}/new_device"
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