Tcsr Inverter (Inv) Bit 8 - Motorola DSP56367 User Manual

Table 13-3 Timer Control Bits for Timers 1 and 2
TC3
0
0
0
0
1
13.3.4.5

TCSR Inverter (INV) Bit 8

The INV bit affects the polarity of the incoming signal on the TIO0 input signal and the
polarity of the output pulse generated on the TIO0 output signal. The effects of the INV bit are
summarized in Table 13-4.
This bit is not in use for timers 1 and 2. It should be left cleared.
TIO0 Programmed as Input
Mode
INV = 0
0 GPIO signal on the TIO0
signal read directly
1 Counter is incremented on
the rising edge of the signal
from the TIO0 signal
2 Counter is incremented on
the rising edge of the signal
from the TIO0 signal
3 Counter is incremented on
the rising edge of the signal
from the TIO0 signal
4 Width of the high input
pulse is measured.
5 Period is measured between
the rising edges of the
input signal.
MOTOROLA
Timer/Event Counter Programming Model
TC2 TC1 TC0
0 0 0
0 0 1
0 1 X
1 X X
X X X
Table 13-4 Inverse Bit
INV = 1
GPIO signal on the TIO0
signal inverted
Counter is incremented on
the falling edge of the
signal from the TIO0 signal
Counter is incremented on
the falling edge of the
signal from the TIO0 signal
Counter is incremented on
the falling edge of the
signal from the TIO0 signal
Width of the low input
pulse is measured.
Period is measured between
the falling edges of the
input signal.
DSP56367
Timer/ Event Counter
Clock Mode
Internal Timer
— Reserved
— Reserved
— Reserved
— Reserved
TIO0 Programmed as Output
INV = 0
Bit written to GPIO put on
TIO0 signal directly
—
TCRx output put on TIO0
signal directly
—
—
—
INV = 1
Bit written to GPIO
inverted and
put on
TIO0 signal
—
TCRx output inverted and
put on TIO0 signal
—
—
—
13-9