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rtc_timedate

rtc_timedate#

Overview#

The RTC project is a demonstration program of the SDK RTC driver working on time date mode. The program does the followings:

  1. Set the stored time and date to make RTC work in timedate mode.

  2. Set watchdog

  3. Set tamper. Write stored security key into RTC. When a tamper occurs triggered by press tamper input button, the system will be reset, the time stamp of tamper will log out and the prestore security key will be erased and log out.

  4. 3 alarms are enabled, alarm0 is single shot, alarm1 and alarm2 are repeated. Alarm1 occurs every second at 80th hundredth. Alarm2 occurs every minute at 2nd second 60th hundredth. In the alarm1 interrupt handler, the watchdog is fed.

Supported Boards#

FRDM-MCXL255
Hardware requirements

  • Type-C USB cable

  • FRDM-MCXL255 board

  • Personal Computer

Board settings

Make sure you have solder bridges SJ1 and SJ2 set to

  • 2-1 for the main core (cm33)

Prepare the Demo

  1. Connect a USB Type-C cable between the host PC and the MCU-Link USB port (J16) on the target board.

  2. Open a serial terminal with the following settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.

Running the demo

The following lines are printed to the serial terminal when the demo program is executed.

```
RTC Time/Date Mode Example

Current Date/Time: 2025-5-31 21:40:0:5 Tamper 0 is enabled, press the button SW6 to trigger it. Stored 256 bit key data written to RTC: Key[0]: 0x12345678 Key[1]: 0x9ABCDEF0 Key[2]: 0x11223344 Key[3]: 0x55667788 Key[4]: 0x99AABBCC Key[5]: 0xDDFF2211 Key[6]: 0x22334455 Key[7]: 0x66778899 Relevant 128 bit key data read from RTC: Key[0]: 0x5678 Key[1]: 0xDEF0 Key[2]: 0x3344 Key[3]: 0x7788 Key[4]: 0xBBCC Key[5]: 0x2211 Key[6]: 0x4455 Key[7]: 0x8899 Alarm 0 will ring at 21:40:04. Alarm 1 will ring every second at 80. Alarm 2 will ring every minute at 2nd second 60 hundredth. Current Date/Time: 2025-5-31 21:40:0:80

*** ALARM 1 occured! ***

*** WATCHDOG fed! *** Current Date/Time: 2025-5-31 21:40:1:80

*** ALARM 1 occured! ***

*** WATCHDOG fed! *** Current Date/Time: 2025-5-31 21:40:2:60

*** ALARM 2 occured! *** Current Date/Time: 2025-5-31 21:40:2:80

*** ALARM 1 occured! ***

*** WATCHDOG fed! *** Current Date/Time: 2025-5-31 21:40:3:80

*** ALARM 1 occured! ***

*** WATCHDOG fed! *** Current Date/Time: 2025-5-31 21:40:4:0

*** ALARM 0 occured! *** Current Date/Time: 2025-5-31 21:40:4:80

*** ALARM 1 occured! ***

*** WATCHDOG fed! *** Current Date/Time: 2025-5-31 21:40:5:80


If you press the tamper input button SW6 to trigger the tamper, the program will be reset, the time stamp of tamper occurs will be captured and log out. The security key will be erased and log out. 

##### ```
##### RTC Time/Date Mode Example
CPU is reset from tamper.
Since the tamper occurs, the 256 bit security key data has been erased. Here is the 128 bit key data read from RTC:
  Key[0]: 0x0
  Key[1]: 0x0
  Key[2]: 0x0
  Key[3]: 0x0
  Key[4]: 0x0
  Key[5]: 0x0
  Key[6]: 0x0
  Key[7]: 0x0
*** TAMPER 0 timestamp: 2025-5-31 21:40:18:40 ***
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