Sonic Alert msm80154s Clock Radio User Manual


 
INTERNAL SPECIFICATIONS
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4.5.2.5.8 Caution about use of timer counters 0 and 1 when setting software power
down mode
When setting sofware power down mode, if the value of a timer counter by which a timer
interrupt is set is immediately before overflow, the software power down mode can not be set.
(Example)
Timer 0 is in mode 1 of external clock.
Content of timer 0 is "FF".
Interrupt by timer 0 is enabled.
TO pin is "1".
If the above conditions all are established, the sofware power down mode cannot be set. This
is because the AND output, shown as (A) of Fig. 4-19, becomes "1" when the software power
down mode is set and timer interrupt is generated.
In this case, set the software power down mode after setting the TO pin to "0".