Hitachi 65 - Hardware System Clock; Table 5-19 Hardware System Clock Specification

5. SPECIFICATION
5-17
5.8 Hardware System Clock
This equipment has a hardware system clock that uses an RTC (real-time clock) IC.
The clock has a built-in calendar and continues to work using a backup battery even when
the system power is off.
Table 5-19 Hardware System Clock Specification
Item
Specifications
Time function
Hour/Minute/Second
(24-hours clock)
Date function
Year/Month/Date
Precision
± 4 seconds per day (*)
Battery
backup
Lithium battery
(*) Rough estimates when the ambient temperature is 25C.
For your information, the system program normally updates the internal clock by using a
periodic timer. The internal clock is adjusted by reading the time and date from the hardware
clock when, for example, the system starts.