189
μ
PD17717, 17718, 17719
13.6.6 Error of timer 3
Timer 3 has an error of up to 1 basic clock in the following cases.
(1) On starting/stopping counter
The counter is started or stopped by setting the TM3EN flag.
Therefore, an error of 0 to +1 clocks occurs when the TM3EN flag is set, and an error of –1 to 0 clocks
occurs when the flag is reset.
In all, an error of
±
1 count occurs.
(2) On resetting counter operation
An error of 0 to +1 clocks occurs when the counter is reset.
(3) On selecting basic clock during counter operation
An error of 0 to +1 clocks of the newly selected clock occurs.
13.6.7 Cautions on using timer 3
Timer 3 interrupt may occur simultaneously with the other timer interrupts and CE reset. If it is necessary
to update the timer at CE reset, do not use timer 3, use basic timer 0 instead.
When timer 3 is used, the three output port pins multiplexed with the D/A converter pins, P1B2/PWM2 through
P1B0/PWM0, are automatically set in the general-purpose output port mode.