CP3BT23 Datasheet, PDF (184/260 Pages) Texas Instruments – CP3BT23 Reprogrammable Connectivity Processor with Bluetooth and Dual CAN Interfaces

25.2.3 Mode 3: Dual Independent Timer/Counter
ue. In addition, the TA pin is toggled on each underflow if this
Mode 3 is the Dual Independent Timer mode, which gener-
ates system timing signals or counts occurrences of exter-
nal events.
Figure 100 is a block diagram of the Multi-Function Timer
configured to operate in Mode 3. The timer is configured to
operate as a dual independent system timer or dual external
event counter. In addition, Timer/Counter 1 can generate a
50% duty cycle PWM signal on the TA pin. The TB pin can
function is enabled by the TAEN bit. The initial state of the
TA pin is software-programmable. When the TA pin is tog-
gled from low to high, it sets the TCPND interrupt pending
bit and also generates an interrupt if enabled by the TAIEN
bit.
Because the TA pin toggles on every underflow, a 50% duty
cycle PWM signal can be generated on the TA pin without
any further action from the CPU.
be used as an external event input or pulse-accumulate in- Timer/Counter 2 (TCNT2) counts down at the rate of the se-
put and can be used as the clock source for either Timer/ lected clock. On underflow, it is reloaded from the TCRB
Counter 1 or Timer/Counter 2. Both counters can also be register and counting proceeds down from the reloaded val-
clocked by the prescaled System Clock.
ue. In addition, each underflow sets the TDPND interrupt
Timer/Counter 1 (TCNT1) counts down at the rate of the se- ^{pending bit and generates an interrupt if the interrupt is en-}
lected clock. On underflow, it is reloaded from the TCRA ^{abled by the TDIEN bit.}
register and counting proceeds down from the reloaded val-
te Timer 1
Clock
le _{Timer 2}
Clock
Reload A
TCRA
Underflow
Timer/Counter 1
TCNT1
Reload B
TCRB
Underflow
Timer/Counter 2
TCNT2
TAPND
TAIEN
TAEN
TDIEN
TDPND
Timer
Interrupt 1
TA
Timer
Interrupt 2
o _Clock
Selector
TB
DS086
Obs^{Figure 100. Dual-Independent Timer/Counter Mode}
183
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