MC68HC908RF2 Datasheet, PDF (202/254 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Timer Interface Module (TIM)
15.5.1 TIM Counter Prescaler
The TIM clock source can be one of the seven prescaler outputs or the
TIM clock pin, TCLK. The prescaler generates seven clock rates from
the internal bus clock. The prescaler select bits, PS[2:0], in the TIM
status and control register select the TIM clock source.
15.5.2 Input Capture
With the input capture function, the TIM can capture the time at which an
external event occurs. When an active edge occurs on the pin of an input
capture channel, the TIM latches the contents of the TIM counter into the
TIM channel registers, TCHxH and TCHxL. The polarity of the active
edge is programmable. Input captures can generate TIM CPU interrupt
requests.
NOTE: TIM channel 1 should not be configured in this mode.
15.5.3 Output Compare
With the output compare function, the TIM can generate a periodic pulse
with a programmable polarity, duration, and frequency. When the
counter reaches the value in the registers of an output compare channel,
the TIM channel 0 can set, clear, or toggle the channel pin. Output
compares can generate TIM CPU interrupt requests for both TIM
channel 0 and TIM channel 1.
NOTE: TIM channel 1 does not have an external pin associated with it.
15.5.4 Unbuffered Output Compare
Any output compare channel can generate unbuffered output compare
pulses as described in 15.5.3 Output Compare. The pulses are
unbuffered because changing the output compare value requires writing
the new value over the old value currently in the TIM channel registers.
Advance Information
202
Timer Interface Module (TIM)
MC68HC908RF2 — Rev. 1
MOTOROLA