Real-Time \ Clock and Battery

General Notes on the Real-Time Clock

Note

The real-time clock is an optional function for AC500-eCo CPUs PM55x and PM56x.

The real-time clock operates as a PC clock. It saves date and time to a DWORD in DT format (DATE AND TIME FORMAT), i.e., in seconds passed since the start time: 1 January 1970 at 00:00.

If a battery is connected and full, the real-time clock continues to run even if the control voltage is switched off.

If no battery is inserted or the battery is empty, the real-time clocks starts with the value 0 (=1970-01-01, 00:00:00).

When switching on the control voltage, the system clock of the operating system is set to the value of the real-time clock.

• The Real-Time Clock
• The AC500 Battery