MC68HC11G5 Datasheet, PDF (139/195 Pages) Motorola, Inc – High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcontroller

Freescale Semiconductor, Inc.
11.3.3.9
Output Unit (EVO)
This unit controls the output signal from the PWM unit. If the EVOEN bit in the EVCTL register is set
to one, the EVO unit is enabled. The state of the EVPOL bit in the EVCTL register then determines
the polarity of the event output. If EVO is not required for pulse width modulation, the EVOEN bit
should be reset to zero to disable the EVO unit and to allow pin PH6 to be used for general purpose
I/O.
11.4 MODE 2: 8-BIT PWM WITH PERIOD COUNTER
In mode 2, the event counter operates as an 8-bit PWM unit and an 8-bit counter (the PA unit)
which increments at the end of each period of the PWM unit. If mode 2 is selected (EVMDB = 1,
EVMDA = 0), then the elements of the event counter are configured as shown in Figure 11-4.
E
E/2
E/4
E/8
E/16
E/32
E/64
E/128
EVI1(PH5)
INPUT1
CLEAR
EVCNT2
8
ECMP2A
8
ECMP2B
CLEAR
EVCNT1
8
ECMP1A
8
ECMP1B
EVENT2
EVENT1
R
(PH6) EVO
S
Figure 11-4. 8-bit PWM with Period Counter (Mode 2)
EVENT COUNTER
11-9
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