DART-MX8M RTC: Difference between revisions
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= Wake-up using the RTC = | = Wake-up using the RTC = | ||
Wake-up using the RTC requires hardware connection of RTC IRQ pin to a SoC GPIO.<br> | Wake-up using the RTC requires hardware connection of RTC IRQ pin to a SoC GPIO.<br> | ||
On DART-MX8M and DART-MX8M- | On DART-MX8M, DART-MX8M-MINI and DART-MX8M-PLUS carrier boards RTC IRQ pin is connected to GPIO1_15.<br> | ||
On VAR-SOM-MX8M-MINI | On VAR-SOM-MX8M-MINI, VAR-SOM-MX8M-NANO VAR-SOM-MX8M-PLUS carrier boards RTC IRQ pin is not connected.<br> | ||
== Using rtcwake command == | == Using rtcwake command == |
Revision as of 17:51, 2 November 2020
DART-MX8M - Real Time Clock (RTC)
Setting the RTC
First set the system date & time:
# date --set="20171231 23:59"
Then set the HW RTC using the system date & time:
# hwclock --systohc --utc
Power down your board, wait 5 minutes and power up again, then check you system date & time and verify it is correct:
# date
Wake-up using the RTC
Wake-up using the RTC requires hardware connection of RTC IRQ pin to a SoC GPIO.
On DART-MX8M, DART-MX8M-MINI and DART-MX8M-PLUS carrier boards RTC IRQ pin is connected to GPIO1_15.
On VAR-SOM-MX8M-MINI, VAR-SOM-MX8M-NANO VAR-SOM-MX8M-PLUS carrier boards RTC IRQ pin is not connected.
Using rtcwake command
For example, to set the RTC to wakeup after 10 seconds type:
# echo enabled > /sys/class/rtc/rtc0/device/power/wakeup # rtcwake -m mem -d rtc0 -s 10
For more options, like waking up at a specific time, run:
# rtcwake --help