mc68hc908mr8 Freescale Semiconductor, Inc, mc68hc908mr8 Datasheet - Page 220

• Manufacturer Part Number: mc68hc908mr8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Timer Interface A (TIMA)
Technical Data
220
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
(TASC).
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 B, and pin PTBx/TCHxA 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.
MSxB:MSxA
X0
X1
00
00
00
01
01
01
1X
1X
1X
Table 11-2. Mode, Edge, and Level Selection
Timer Interface A (TIMA)
ELSxB:ELSxA
00
00
01
10
11
01
10
11
01
10
11
compare
compare
Buffered
or PWM
buffered
capture
Output
Output
preset
output
Mode
PWM
Input
or
Table 11-2
Pin under port control:
Initialize timer
Output level high
Pin under port control:
Initialize timer
Output level low
Capture on rising edge only
Capture on falling edge only
Capture on rising or falling edge
Toggle output on compare
Clear output on compare
Set output on compare
Toggle output on compare
Clear output on compare
Set output on compare
MC68HC908MR8 — Rev 4.1
Configuration
Freescale Semiconductor
shows how ELSxA