Chapter 3
Connecting the Signals
DAQPad-MIO-16XE-50 User Manual
3-38
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GPCTR0_GATE Signal
Any PFI signal can externally input GPCTR0_GATE, which is available as
an output on the PFI9/GPCTR0_GATE screw terminal.
As an input, the GPCTR0_GATE signal is configured in the edge-detection
mode. You can select any PFI signal as the source for GPCTR0_GATE and
configure the polarity selection for either rising or falling edge. You can use
the gate signal in a variety of different applications to perform actions such
as starting and stopping the counter, generating interrupts, saving the
counter contents, and so on.
As an output, the GPCTR0_GATE signal reflects the actual gate signal
connected to general-purpose counter 0, even if the gate is being externally
generated by another PFI. This output is set to high-impedance at start up.
Figure 3-29 shows the timing requirements for the GPCTR0_GATE signal.
Figure 3-29.
GPCTR0_GATE Signal Timing
GPCTR0_OUT Signal
This signal is available only as an output on the GPCTR0_OUT screw
terminal. The GPCTR0_OUT signal reflects the terminal count (TC)
of general-purpose counter 0. 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
high-impedance at start up. Figure 3-30 shows the timing of the
GPCTR0_OUT signal.
Rising-Edge
Polarity
Falling-Edge
Polarity
t
w
= 10 ns minimum
t
w