Datasheet

C167CS-4R
C167CS-L
Data Sheet 29 V2.2, 2001-08
Real Time Clock
The Real Time Clock (RTC) module of the C167CS consists of a chain of 3 divider
blocks, a fixed 8:1 divider, the reloadable 16-bit timer T14, and the 32-bit RTC timer
(accessible via registers RTCH and RTCL). The RTC module is directly clocked with the
on-chip oscillator frequency divided by 32 via a separate clock driver (
f
RTC
= f
OSC
/32)
and is therefore independent from the selected clock generation mode of the C167CS.
All timers count up.
The RTC module can be used for different purposes:
• System clock to determine the current time and date
• Cyclic time based interrupt
• 48-bit timer for long term measurements
Figure 8 RTC Block Diagram
Note: The registers associated with the RTC are not affected by a reset in order to
maintain the correct system time even when intermediate resets are executed.
MCD04432
T14REL
T14 8:1
RTC
f
RTCLRTCH
Interrupt
Request
Reload