MC68HC908LJ24 Datasheet, PDF (244/464 Pages) Motorola, Inc – Microcontrollers

Real Time Clock (RTC)
12.10.13 Day-Of-Week Register (DOWR)
This read/write register contains the current value of the day-of-week
counter. This register can be read at any time without affecting the
counter count. Writing to this register loads the value to the day-of-week
counter and the counter continues to count from this new value.
The day-of-week counter value rolls over to 0 ($00) after reaching 6
($06). Writing a value other than 0 to 6 to this register has no effect.
Address: $004D
Read: 0
0
0
0
0
DOW2 DOW1
Write:
Reset: 0
0
0
0
0
U
U
= Unimplemented
This register is write-protected; unprotect by a write sequence to RTCWE[1:0] in RTCCOMR.
Figure 12-19. Day-Of-Week Register (DOWR)
DOW0
U
12.10.14 Chronograph Data Register (CHRR)
This read-only chronograph data register contains the value in the
chronograph counter. Reset clears the chronograph data register.
Setting the chronograph counter reset bit (CHRCLR) also clears the
chronograph data register.
The chronograph data register has a resolution of 1/100 seconds. The
chronograph counter value rolls over to $00 after reaching $63.
Address: $004E
Read: 0
CHR6
CHR5
CHR4
CHR3
CHR2
CHR1
Write:
Reset: 0
0
0
0
0
0
0
= Unimplemented
Figure 12-20. Chronograph Data Register (CHRR)
CHR0
0
NOTE:
The chronograph counter is not synchronized to the compensated RTC
1-Hz clock. Hence, chronograph ticks may not align with the RTC clock
and calendar register updates.
Data Sheet
244
Real Time Clock (RTC)
MC68HC908LJ24/LK24 — Rev. 2.1
Freescale Semiconductor