DESK-MP1-L/Peripherals/RTC
| HOME | SOMs | SBCs | ToloMEO Embedded Assistant |  GET A QUOTE
|
 ONLINE HELPDESK
|
| Roadmap | IoT Services | ML/AI services | Embedded Design Services |
| History | |||
|---|---|---|---|
| Issue Date | Notes | ||
| 2023/08/02 | DESK-MP1-L-1.0.0 release | ||
Contents
Pheripheral RTC[edit | edit source]
On SBC ETRA there are two rtc one on ETRA SOM and one on carrier board.
root@desk-mp1:~# ls -la /dev/rtc* lrwxrwxrwx 1 root root 4 Aug 2 10:45 /dev/rtc -> rtc0 crw------- 1 root root 253, 0 Aug 2 10:45 /dev/rtc0 crw------- 1 root root 253, 1 Aug 2 10:45 /dev/rtc1
Device tree configuration[edit | edit source]
...
...
&i2c4{
...
...
ds3232: rtc@68 {
compatible = "dallas,ds3232";
reg = <0x68>;
interrupt-parent = <&gpiod>;
interrupts = <6 IRQ_TYPE_EDGE_FALLING>;
status = "okay";
};
...
...
};
...
...
&rtc{
status = "okay";
/* USER CODE BEGIN rtc */
/* USER CODE END rtc */
};
...
...
Linux messages at boot time[edit | edit source]
... [ 2.006753] stm32_rtc 5c004000.rtc: registered as rtc0 [ 2.010619] stm32_rtc 5c004000.rtc: setting system clock to 2023-08-02T10:45:30 UTC (1690973130) [ 2.019926] stm32_rtc 5c004000.rtc: registered rev:1.2 ... [ 2.177792] rtc-ds3232 1-0068: registered as rtc1 ...
Usage with hwclock[edit | edit source]
root@desk-mp1:~# hwclock -f /dev/rtc1 -v hwclock from util-linux 2.37.4 System Time: 1690975162.373458 Using the rtc interface to the clock. Assuming hardware clock is kept in UTC time. Waiting for clock tick... ...got clock tick Time read from Hardware Clock: 2023/08/02 11:19:24 Hw clock time : 2023/08/02 11:19:24 = 1690975164 seconds since 1969 Time since last adjustment is 1690975164 seconds Calculated Hardware Clock drift is 0.000000 seconds 2023-08-02 11:19:23.549038+00:00
