M41T93
Clock operation
3.8.5
Note:
TD1/0
These are the timer source clock frequency selection bits (see Table 9). These bits
determine the source clock for the countdown timer (see Table 10). When not in use, the
TD1 and TD0 Bits should be set to ‘11’ (1/60Hz) for power saving.
Table 9.
Timer source clock frequency selection (244.1µs to 4.25 hrs)
TD1
TD0
Timer source clock frequency (Hz)
0
0
4096 (244.1µs)
0
1
64 (15.6ms)
1
0
1
1
1 (1s)
1/60 (60s)
Table 10. Timer countdown value register bits (addr 11h)
Bit
Symbol
Description
7-0
<timer countdown This register holds the loaded countdown value ‘n.’
value>
Countdown Period = n / Source Clock frequency.
Writing to the timer register will not reset the TF Bit or clear the interrupt.
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