
Timer Interface Module (TIM1)
MC68HC08GR32A MC68HC08GR16A Data Sheet, Rev. 0
218
Freescale Semiconductor
17.9.4 TIM1 Channel Status and Control Registers
Each of the TIM1 channel status and control registers does the following:
Flags input captures and output compares
Enables input capture and output compare interrupts
Selects input capture, output compare, or PWM operation
Selects high, low, or toggling output on output compare
Selects rising edge, falling edge, or any edge as the active input capture trigger
Selects output toggling on TIM1 overflow
Selects 0% and 100% PWM duty cycle
Selects buffered or unbuffered output compare/PWM operation
CHxF — Channel x Flag Bit
When channel x is an input capture channel, this read/write bit is set when an active edge occurs on
the channel x pin. When channel x is an output compare channel, CHxF is set when the value in the
TIM1 counter registers matches the value in the TIM1 channel x registers.
Clear CHxF by reading the TIM1 channel x status and control register with CHxF set and then writing
a 0 to CHxF. If another interrupt request occurs before the clearing sequence is complete, then writing
0 to CHxF has no effect. Therefore, an interrupt request cannot be lost due to inadvertent clearing of
CHxF.
Reset clears the CHxF bit. 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 TIM1 CPU interrupt service requests on channel x. Reset clears the CHxIE
bit.
1 = Channel x CPU interrupt requests enabled
0 = Channel x CPU interrupt requests disabled
MSxB — Mode Select Bit B
This read/write bit selects buffered output compare/PWM operation. MSxB exists only in the TIM1
channel 0 status and control register.
Address: $0025
T1SC0
Bit 7
654321
Bit 0
Read:
CH0F
CH0IE
MS0B
MS0A
ELS0B
ELS0A
TOV0
CH0MAX
Write:
0
Reset:
00000000
Address: $0028
T1SC1
Bit 7
654321
Bit 0
Read:
CH1F
CH1IE
0
MS1A
ELS1B
ELS1A
TOV1
CH1MAX
Write:
0
Reset:
00000000
= Unimplemented
Figure 17-8. TIM1 Channel Status and Control
Registers (T1SC0:T1SC1)