Freescale Semiconductor DSP56366 - Manual (Page 239)

Timer/Event Counter Programming Model
DSP56366 24-Bit Digital Signal Processor User Manual, Rev. 4
Freescale Semiconductor 11-9
11.3.4.5 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 11-4 .
This bit is not in use for timers 1 and 2. It should be left cleared.
The INV bit is cleared by the hardware RESET signal or the software RESET instruction.
Table 11-4 Inverter (INV) Bit Operation
Mode
TIO0 Programmed as Input TIO0 Programmed as Output
INV = 0 INV = 1 INV = 0 INV = 1
0 GPIO signal on the TIO0
signal read directly GPIO signal on the TIO0
signal inverted Bit written to GPIO put on
TIO0 signal directly Bit written to GPIO
inverted and
put on
TIO0 signal
1 Counter is incremented on
the rising edge of the
signal from the TIO0 signal Counter is incremented on
the falling edge of the
signal from the TIO0 signal — —
2 Counter is incremented on
the rising edge of the
signal from the TIO0 signal Counter is incremented on
the falling edge of the
signal from the TIO0 signal TCRx output put on TIO0
signal directly TCRx output inverted and
put on TIO0 signal
3 Counter is incremented on
the rising edge of the
signal from the TIO0 signal Counter is incremented on
the falling edge of the
signal from the TIO0 signal — —
4 Width of the high input
pulse is measured. Width of the low input pulse
is measured. — —
5 Period is measured
between the rising edges
of the input signal. Period is measured
between the falling edges
of the input signal. — —
6 Event is captured on the
rising edge of the signal
from the TIO0 signal Event is captured on the
falling edge of the signal
from the TIO0 signal — —
7 — — Pulse generated by the
timer has positive polarity Pulse generated by the
timer has negative polarity
9 — — Pulse generated by the
timer has positive polarity Pulse generated by the
timer has negative polarity
10 — — Pulse generated by the
timer has positive polarity Pulse generated by the
timer has negative polarity