Tcsr Timer Reload Mode (Trm) Bit 9 - Motorola DSP56367 User Manual

Timer/ Event Counter
Timer/Event Counter Programming Model
TIO0 Programmed as Input
Mode
INV = 0
6 Event is captured on the
rising edge of the signal
from the TIO0 signal
7 —
9 —
10 —
The INV bit is cleared by the hardware RESET signal or the software RESET instruction.
Note: The INV bit affects both the timer and GPIO modes of operation. To ensure
correct operation, this bit should be changed only when one or both of the
following conditions is true:
• The timer has been disabled by clearing the TE bit in the TCSR.
• The timer is in GPIO mode.
The INV bit does not affect the polarity of the prescaler source when TIO0 is used as input to
the prescaler.
13.3.4.6

TCSR Timer Reload Mode (TRM) Bit 9

The TRM bit controls the counter preload operation.
In timer (0–3) and watchdog (9–10) modes, the counter is preloaded with the TLR value after
the TE bit is set and the first internal or external clock signal is received. If the TRM bit is set,
the counter is reloaded each time after it reaches the value contained by the TCR. In PWM
mode (7), the counter is reloaded each time counter overflow occurs. In measurement (4–5)
modes, if the TRM and the TE bits are set, the counter is preloaded with the TLR value on
each appropriate edge of the input signal.
If the TRM bit is cleared, the counter operates as a free-running counter and is incremented on
each incoming event. The TRM bit is cleared by the hardware RESET signal or the software
RESET instruction.
13.3.4.7 TCSR Direction (DIR) Bit 11
The DIR bit determines the behavior of the TIO0 signal when it is used as a GPIO pin. When
the DIR bit is set, the TIO0 signal is an output; when the DIR bit is cleared, the TIO0 signal is
13-10
Table 13-4 Inverse Bit
INV = 1
Event is captured on the
falling edge of the signal
from the TIO0 signal
— Pulse generated by the
timer has positive polarity
— Pulse generated by the
timer has positive polarity
— Pulse generated by the
timer has positive polarity
DSP56367
TIO0 Programmed as Output
INV = 0
—
Pulse generated by the timer
has negative polarity
Pulse generated by the timer
has negative polarity
Pulse generated by the timer
has negative polarity
MOTOROLA
INV = 1
—