mc68hc908mr24 Freescale Semiconductor, Inc, mc68hc908mr24 Datasheet - Page 251

• Manufacturer Part Number: mc68hc908mr24
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

MC68HC908MR24 — Rev. 4.1
Freescale Semiconductor
NOTE:
NOTE:
Before changing a channel function by writing to the MSxB or MSxA bit,
set the TSTOP and TRST bits in the TIMB status and control register
(TBSC).
ELSxB and ELSxA — Edge/Level Select Bits
Before enabling a TIMB channel register for input capture operation,
make sure that the PTEx/TBCHx pin is stable for at least two bus clocks.
TOVx — Toggle-On-Overflow Bit
When ELSxB:A = 00, this read/write bit selects the initial output level
of the TCHx pin once PWM, input capture, or output compare
operation is enabled. See
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, and pin PTEx/TCHxB 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,
or output compare mode is enabled.
and ELSxA work. Reset clears the ELSxB and ELSxA bits.
When channel x is an output compare channel, this read/write bit
controls the behavior of the channel x output when the TIMB counter
overflows. When channel x is an input capture channel, TOVx has no
effect. Reset clears the TOVx bit.
1 = Initial output level low
0 = Initial output level high
1 = Channel x pin toggles on TIMB counter overflow.
0 = Channel x pin does not toggle on TIMB counter overflow.
Timer Interface B (TIMB)
Table
12-2. Reset clears the MSxA bit.
Table 12-2
Timer Interface B (TIMB)
shows how ELSxB
Advance Information
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