Timer Interface Module (TIM2)
Data Sheet
MC68HC908GZ60 MC68HC908GZ48 MC68HC908GZ32 — Rev. 1.0
316
Timer Interface Module (TIM2)
MOTOROLA
19.3.3.2 Buffered Output Compare
Channels 0 and 1 can be linked to form a buffered output compare channel whose
output appears on the T2CH0 pin. The TIM2 channel registers of the linked pair
alternately control the output.
Setting the MS0B bit in TIM2 channel 0 status and control register (T2SC0) links
channel 0 and channel 1. The output compare value in the TIM2 channel 0
registers initially controls the output on the T2CH0 pin. Writing to the TIM2
channel 1 registers enables the TIM2 channel 1 registers to synchronously control
the output after the TIM2 overflows. At each subsequent overflow, the TIM2
channel registers (0 or 1) that control the output are the ones written to last. T2SC0
controls and monitors the buffered output compare function, and TIM2 channel 1
status and control register (T2SC1) is unused. While the MS0B bit is set, the
channel 1 pin, T2CH1, is available as a general-purpose I/O pin.
Channels 2 and 3 can be linked to form a buffered output compare channel whose
output appears on the T2CH2 pin. The TIM2 channel registers of the linked pair
alternately control the output.
Setting the MS2B bit in TIM2 channel 2 status and control register (T2SC2) links
channel 2 and channel 3. The output compare value in the TIM2 channel 2
registers initially controls the output on the T2CH2 pin. Writing to the TIM2 channel
3 registers enables the TIM2 channel 3 registers to synchronously control the
output after the TIM2 overflows. At each subsequent overflow, the TIM2 channel
registers (2 or 3) that control the output are the ones written to last. T2SC2 controls
and monitors the buffered output compare function, and TIM2 channel 3 status and
control register (T2SC3) is unused. While the MS2B bit is set, the channel 3 pin,
T2CH3, is available as a general-purpose I/O pin.
Channels 4 and 5 can be linked to form a buffered output compare channel whose
output appears on the T2CH4 pin. The TIM2 channel registers of the linked pair
alternately control the output.
Setting the MS4B bit in TIM2 channel 4 status and control register (T2SC4) links
channel 4 and channel 5. The output compare value in the TIM2 channel 4
registers initially controls the output on the T2CH4 pin. Writing to the TIM2 channel
5 registers enables the TIM2 channel 5 registers to synchronously control the
output after the TIM2 overflows. At each subsequent overflow, the TIM2 channel
registers (4 or 5) that control the output are the ones written to last. T2SC4 controls
and monitors the buffered output compare function, and TIM2 channel 5 status and
control register (T2SC5) is unused. While the MS4B bit is set, the channel 5 pin,
T2CH5, is available as a general-purpose I/O pin.
NOTE:
In buffered output compare operation, do not write new output compare values to
the currently active channel registers. User software should track the currently
active channel to prevent writing a new value to the active channel. Writing to the
active channel registers is the same as generating unbuffered output compares.