s908gr32ag3vfa Freescale Semiconductor, Inc, s908gr32ag3vfa Datasheet - Page 238

• Manufacturer Part Number: s908gr32ag3vfa
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Timer Interface Module (TIM1)
ELSxB and ELSxA — Edge/Level Select Bits
TOVx — Toggle-On-Overflow Bit
238
When ELSxB:A = 00, this read/write bit selects the initial output level of the TCHx pin (see
Reset clears the MSxA bit.
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 an I/O port, and pin TCHx is
available as a general-purpose I/O pin.
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 TIM1 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 TIM1 counter overflow.
0 = Channel x pin does not toggle on TIM1 counter overflow.
MSxB
Before changing a channel function by writing to the MSxB or MSxA bit, set
the TSTOP and TRST bits in the TIM1 status and control register (T1SC).
After initially enabling a TIM1 channel register for input capture operation
and selecting the edge sensitivity, clear CHxF to ignore any erroneous
edge detection flags.
X
X
0
0
0
0
0
0
0
1
1
1
MC68HC908GR60A • MC68HC908GR48A • MC68HC908GR32A Data Sheet, Rev. 5
MSxA
X
X
X
0
1
0
0
0
1
1
1
1
Table 17-2. Mode, Edge, and Level Selection
ELSxB
0
0
0
1
1
0
0
1
1
0
1
1
ELSxA
0
0
1
0
1
0
1
0
1
1
0
1
Table 17-2
Output compare
buffered PWM
NOTE
NOTE
Output preset
Input capture
compare or
Buffered
or PWM
output
Mode
shows how ELSxB and ELSxA work. Reset clears
Pin under port control;
initial output level high
Pin under port control;
initial output level low
Capture on rising edge only
Capture on falling edge only
Capture on rising
or falling edge
Software compare only
Toggle output on compare
Clear output on compare
Set output on compare
Toggle output on compare
Clear output on compare
Set output on compare
Configuration
Freescale Semiconductor
Table
17-2).