Ni usb-6001/6002/6003 User Guide National Instruments
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code vf-s11, BÁO CÁO MÔN ĐƯỜNG LỐI, bao cao mon hoc trang bị
- Điều hướng trang này:
- Figure 15.
| Figure 14.
Example of Connecting an External User-Provided Resistor For more information about configuring NI devices to be open-drain (open collector) or push-pull (active drive), go to ni.com/info and enter Info Code ex52sp .
To protect the NI DAQ device against overvoltage, undervoltage, and overcurrent conditions, as well as ESD events, you should avoid these fault conditions by using the following guidelines: • If you configure a DIO line as an output, do not connect it to any external signal source, ground signal, or power supply. • If you configure a DIO line as an output, understand the current requirements of the load connected to these signals. Do not exceed the specified current output limits of the NI DAQ device. National Instruments has several signal conditioning solutions for digital applications requiring high-current drive. • If you configure a DIO line as an input, do not drive the line with voltages outside of its normal operating range. The DIO lines have a smaller operating range than the AI signals. • Treat the NI DAQ device as you would treat any static-sensitive device. Always properly ground yourself and the equipment when handling the NI DAQ device or connecting to it. Note: Ensure that the current flowing across R pull
does not violate the maximum sinking current specifications (4 mA).
External Load
47.5 k Ω Onboard Pull-Down Resistor
External Pull-Up
Resistor DAQ Device P0.0 with Output Drive Type Set to Open Collector V pull-up
(User Provided, ≤5 V)
R pull
47 Ω Protection Resistor NI USB-6001/6002/6003 User Guide | © National Instruments | 23 PFI 0 and PFI 1 Using PFI as a Counter Source You can configure PFI 0 or PFI 1 as a source for counting digital edges. In this mode, either rising- or falling-edges are counted using a 32-bit counter. For more information, refer to the device specifications document available at ni.com/manuals .
Edges can only be counted up from either 0 or an initial value such as 1, 2, 3...or 1001, 1002, 1003. Counting down is not supported; you cannot set the initial count to 100 and count down 99, 98, 97. Using PFI to Trigger an Analog Input Acquisition You can configure an analog input task to wait for an edge on PFI 0 or PFI 1 before starting the acquisition. To do this, configure the AI Start Trigger source to be PFI 0 or PFI 1 and specify either rising or falling edge. Using PFI to Trigger an Analog Output Generation You can configure an analog output task to wait for an edge on PFI 0 or PFI 1 before starting the acquisition. To do this, configure the AO Start Trigger source to be PFI 0 or PFI 1 and specify either rising- or falling-edge. Figure 15 shows the +5 V power source circuitry of the NI USB-6001/6002/6003.
+5 V Power Source Circuitry The main blocks featured in the +5 V power source circuitry are as follows: •
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