MC908QY8CDWE Datasheet, PDF (189/232 Pages) Freescale Semiconductor, Inc – Addendum to MC68HC908QB8, rev. 3

Registers
Writing a 1 to CHxF has no effect.
1 = Input capture or output compare on channel x
0 = No input capture or output compare on channel x
CHxIE — Channel x Interrupt Enable Bit
This read/write bit enables TIM interrupt service requests on channel x.
1 = Channel x interrupt requests enabled
0 = Channel x interrupt requests disabled
MSxB — Mode Select Bit B
This read/write bit selects buffered output compare/PWM operation. MSxB exists only in the TSC0 and
TSC2 registers.
Setting MS0B causes the contents of TSC1 to be ignored by the TIM and reverts TCH1 to
general-purpose I/O.
Setting MS2B causes the contents of TSC3 to be ignored by the TIM and reverts TCH3 to
general-purpose I/O.
1 = Buffered output compare/PWM operation enabled
0 = Buffered output compare/PWM operation disabled
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 16-2.
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 (see Table 16-2).
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 TIM status and control register (TSC).
Table 16-2. Mode, Edge, and Level Selection
MSxB
X
X
0
0
0
0
0
0
0
1
1
1
MSxA
0
1
0
0
0
1
1
1
1
X
X
X
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
Mode
Configuration
Output preset
Pin under port control; initial
output level high
Pin under port control; initial
output level low
Capture on rising edge only
Input capture Capture on falling edge only
Capture on rising or falling edge
Software compare only
Output compare ^{Toggle output on compare}
or PWM
Clear output on compare
Set output on compare
Buffered output
compare or
buffered PWM
Toggle output on compare
Clear output on compare
Set output on compare
MC68HC908QB8 Data Sheet, Rev. 3
Freescale Semiconductor
187