In the user guide for USB-6009 it says on page 17:
"Power-On States
At system startup and reset, the hardware sets all DIO lines to high-impedance inputs. The DAQ device does not drive the signal high or low. Each line has a weak pull-up resistor connected to it."
On page 15 is says:
"Source/Sink Information
The default configuration of the USB-6008/6009 DIO ports is open collector, allowing 5 V operation with an onboard 4.7kOhm pull-up resistor."
NI say that the lines are high-impedance. But then there is a weak pull-up resistor, and the value of that pull-up is 4.7kOhm!?! Is 4.7kOhm really considered the same as high-impedance?
Is there any way of turning off this 4.7kOhm pull-up resistor?
Regards
Jan Egil