User manual

Appendix C Common Questions

function the connected signal serves. Use the Route Signal VI to enable the

PFI lines to output internal signals.

Caution

If you enable a PFI line for output, do not connect any external signal source to

it; if you do, you can damage the device, the computer, and the connected equipment.

What are the power-on states of the PFI and DIO lines on the I/O

connector?

At system power-on and reset, both the PFI and DIO lines are set to high

impedance by the hardware. This setting means that the device circuitry

is not actively driving the output either high or low. However, these lines

may have pullup or pulldown resistors connected to them as shown in

Table 4-2, I/O Signal Summary for the NI 6034E/6035E/6036E.These

resistors weakly pull the output to either a logic-high or logic-low state.

For example, DIO<0> is in the high-impedance state after power on, and

Table 4-2, I/O Signal Summary for the NI 6034E/6035E/6036E, shows the

50 kΩ pullup resistor. This pullup resistor sets the DIO<0> pin to a logic

high when the output is in a high-impedance state.

UM.book Page 5 Monday, May 14, 2001 10:32 AM