GPIB

[labview1958]

My PC has a DAQ card and a serial port. Can I add a GPIB port? What is the difference between a SERIAL and a PARALLEL port?

[Dennis_Knutson]

Yes you can. There are several GPIB options. PCI, USB, Ethernet, PCMCIA, ISA. You can go to NI's main web page and check prices and spec's. Serial and parallel refer to how data is transmitted. Serial transmission sends data one bit at a time over a single line. Data is received in the same manner. Most often over a separate dedicated line. There may be additional lines for handshaking (when to send, when to receive, etc.). Examples of serial data transmission are the RS-232 ports (DB9 or DB25) on a pc though these are less common these days. In these forums, when you see reference to the serial port, it typically refers to the RS232. These are low speed (300 bits/sec to 115kbits/sec). These connect to modems and some instruments. USB or Universal Serial Bus is a high speed serial. They're the little retangular connectors on newer pc's. These connect to mice, keyboards, cameras, and more and more instruments have these connections. Ethernet is another example of serial data transmission. Parallel means several data bits are transmitted simultaneously. Data widths may be 8, 16, 32, etc bits wide. The printer port on your pc is a parallel port. In these forums, when you see reference to the parallel port, it usually means the printer port. GPIB is another parallel data scheme. The PCI and/or ISA slots in a pc use parallel data.

[labview1958]

I have a digital multimeter that is always used with a GPIB. Can it be used with a 6025E DAQ card? How many instruments can be read by a 6025E DAQ card? I have a tachometer that cannot be connected to the 6025E daq card. Can I manually insert it's reading every minute on the front panel while the labview program is in the RUN mode?

[Dennis_Knutson]

I thought we've already covered what your DAQ board can and cannot do. A DAQ and GPIB boards are two completely different things. A DAQ board is an INSTRUMENT. Think of it as a multichannel DMM and function generator all rolled into one. A GPIB board is an interface between a computer and an instrument. It provides for remote control of the instrument.

[labview1958]

I am dealing with voltages up to 30 Volts and currents up to 2 amps. If I connect the equipment to the DAQ 6025E card, which PINS shall I connect to? I have attached a copy of the 50-pin connector from the manual. I need to measure the voltage only.

[labview1958]

Sorry I forgot the attachment file.

[Dennis_Knutson]

As noted in your post here, you could but some signal conditioning hardware to limit the voltages and currents to the 6025. The 6025 has an input range of only +/- 10 volts. You could also do your own with a voltage divider and current limiting circuit. Which pins you connect and how you connect them is up to you. You've got analog channels for input. You can connect them for differential or single-ended measurments. NI sells terminal block accessories that make connections simple. They've got a ribbon cable connector that is used to connect to a DAQ board and screw terminals that you can use for discrete wires connected to whatever you need.

[labview1958]

I am attaching a PWM.VI. I have already sent a 6025E 50-PIN connection table. How do I connect the equipment with the DAQ card? The LV VI is in 6.0.

[JoshuaP]

I think there are a lot of details that are being missed here. Have you considered taking a LabVIEW and/or DAQ training class. National Instruments offers lots of classes around the world and you can find out more about them at www.ni.com/training/.

Joshua Prewitt
National Instruments

[labview1958]

The fees charged are high and the time and place of the training courses somehow are always inconvenient to me. I am willing to pay a small fee to anyone to guide me through the NET. Can you please LIST at least FIVE major errors in the PWM.VI so that I can hit the books.