MC68HC08AZ16 Datasheet, PDF (482/527 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Appendix B: TIMA-6
I/O Registers
MSxA — Mode Select Bit A
When ELSxB:A ≠ 00, this read/write bit selects either input capture
operation or unbuffered output compare/PWM operation. See Table 2
1 = Unbuffered output compare/PWM operation
0 = Input capture operation
When ELSxB:A = 00, this read/write bit selects the initial output level
of the TCHx pin once PWM, output compare mode, or input capture
mode is enabled, see Table 2. Reset clears the MSxA bit.
1 = Initial output level low
0 = Initial output level high
NOTE:
Before changing a channel function by writing to the MSxB or MSxA bit,
set the TSTOP and TRST bits in the TIMA status and control register
(TSC).
ELSxB and ELSxA — Edge/Level Select Bits
When channel x is an input capture channel, these read/write bits
control the active edge-sensing logic on channel x.
When channel x is an output compare channel, ELSxB and ELSxA
control the channel x output behavior when an output compare
occurs.
When ELSxB and ELSxA are both clear, channel x is not connected
to port E or port F, and pin PTEx/TACHx or pin PTFx/TACHx is
available as a general-purpose I/O pin. However, channel x is at a
state determined by these bits and becomes transparent to the
respective pin when PWM, input capture mode, or output compare
operation mode is enabled. Table 2 shows how ELSxB and ELSxA
work. Reset clears the ELSxB and ELSxA bits.
25-tima6
MOTOROLA
Appendix B: TIMA-6
MC68HC08AZ32
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