Chapter 4
Signal Connections
4-38
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GPCTR1_OUT Signal
This signal is available only as an output on the GPCTR1_OUT pin.
The GPCTR1_OUT signal monitors the TC device general-purpose
counter 1. You have two software-selectable output options—pulse on TC
and toggle output polarity on TC. The output polarity is software-selectable
for both options. This output is set to tri-state at startup. Figure 4-34 shows
the timing requirements for the GPCTR1_OUT signal.
Figure 4-34.
GPCTR1_OUT Signal Timing
GPCTR1_UP_DOWN Signal
This signal can be externally input on the DIO7 pin and is not available as
an output on the I/O connector. General-purpose counter 1 counts down
when this pin is at a logic low and counts up at a logic high. This input can
be disabled so that software can control the up-down functionality and
leave the DIO7 pin free for general use. Figure 4-35
shows the timing
requirements for the GATE and SOURCE input signals and the timing
specifications for the OUT output signals of your device.
Rising-Edge
Polarity
Falling-Edge
Polarity
t
w
t
w
= 10 ns minimum