Multi-channel Scan

i am using PCI-6025E DAQ card. do Multi-channel Scan
,before signal input to analog input , i use a voltage follower ad623. sample frequency is 1k, is it safe ?
or how to reduce settling time effect ?

Hi Schmidt,
The input range for the 6025E board is +/- 10 V, so if your signal (going into the DAQ board) is within this range you are safe. In regards to reducing settling time, you are on the right track. The following link is a great resource when using a voltage follower to reduce the impedance of a transducer.
http://zone.ni.com/devzone/conceptd.nsf/webmain/CD57A73721E0612586256BAE0055CDD9?opendocument&node=dz00000_us
Have a great day!
Brooks W.
National Instruments

Similar Messages

Multi channel continuous DAQ acquisition

Complete newbie question here. First time using Labview so I apologize for asking this question: Is it possible to have multi channel contiuous acquisition? If so, does this have to go through a circular buffer to prevent tying up all the computer memory? Can you vary the scan and read rates for each channel? Last question: If it is possible to do all of the above....how do you do it? I've attached a .pdf file with screen shots of my front panel and block diagram....it's extremely crude just trying to get some basic concepts down. Also if anyone can recommend some good books on actually doing the wiring and conditions of the various elements, I'd be extremely grateful. Currently I have "Labview for Everyone".
Attachments:
DAQ.pdf ‏33 KB

Hello,
It is possible to have a multi channel continuous acquisition and it does use a circular buffer. Please check out the Continuous Waveform Acquisition Tutorial for more information about how this is done. With our DAQ devices you can use different sampling frequencies as long as they have a common divisor and the sampling rates remain within the device specifications. There is an example of that called Multi-Rate Continuous Analog Input.
The example finder is always a useful place to look for ideas on how to make a VI. In LabVIEW, go to Help->Find Examples and you will open up a browser that will allow you to look through many examples. You can also check out the LabVIEW Zone Learning Center where you can find a book listing under the fundamentals section.
Hope this helps!
Laura F.

How can I use all tracks from multi-channel source audio with Multicam clips?

I cannot figure this out. Working in Premiere I'm prepping for a 2 camera show, with typically 4 to 6 track dual-system audio recorded by the sound guy. I can sync, and make multicam clips any number of ways–whether sync by timecode, sync by audio, or eyeballing–but whenever I edit using the MC clip, Premiere mixes down all the audio channels into a stereo single track, and I cannot pick and choose which audio track from the original to use. With 2-5 people mic'd on lavs, I need to be able to choose which audio is either cut in or heard at any given shot.
Is there any way to have control in multicam clips over which track of audio gets edited into the timeline, or even: that all tracks of audio get cut in? It's very important for the editors to be able to see waveform (which also disappears for some reason in the mixdown) and pick and choose which audio is heard?
I'm sure this might be a simple fix, but I cannot get my head around it for workflow purposes for my assistant editors. We need to use multicam, but this audio thing is driving all of us crazy. None of us can figure out how to have a multicam clip and use it with control over what audio is cut in.

True, but what I need to be able to do is have my multicam sequence in the source monitor, and cut into my working sequence with either just the audio I need from the sound guy's multi-channel WAV, OR cut in all the sound and from then I can just enable or disable what I need or don't need. But also be able to match back to the Multicam source from my working sequence.
I don't want to have to open the synced sequence, and razor blade the things I need and have to copy and paste into my working sequence in order to have the full spectrum of my multi-channel mono lav WAV files...with their waveforms visible.
Essentially, I want my Multicam clips to load in the source monitor, and the ability to cut them into the working sequence without it mixing down the audio into a single track with no visible waveform–which is what it is doing currently. Can I choose to edit in either ALL of the tracks of the WAV file along with the camera shot I want, or control which audio gets cut in?

Important question: I have got a PXI-4472 and I am able to do single-channel acquisition. How does multi-channel acquisition work?

Look at the VI: it is quite eleborate, but the crucial point is Data Acquisition and Trigger&Gate (and, consequentely, Write to File operation).
I can add plot on the Waveform Graph DATA, this is rather easy, simply adding the channel numbers in the channel control (es. writing 0,3,7 will collect data from the three channels).
First question: is this operation of adding plots correct?
Second question: does the sampling rate dwindle when I consider multi-channel acquisition? I mean: 1 channel-->100KHz ; 2 channels-->50 KHz
More over, and MORE IMPORTANT: is it possible to set different trigger conditions for different channel
s? How can I control this operation?
Third: can you have a look at the VI as all (the appearence, the functionality, the logical sequence...). I am looking forward to get your advice. In particular:
Look at the frontal panel: what do you suggest to make it "smaller"? More tab controls?
Look at the Block Diagram: do I have to connect ERROR IN and ERROR OUT to every suVI or function that makes this connection possible (as Trigger&Gate and Write File)?
Attachments:
Start&StopTrig_SpectralMeas_style+image.vi ‏700 KB

First: yes, the operation is correct.
Second: yes again. When you consider a multi-channel acquisition, your sampling rate must be shared among the channels.
Third: when you specify a list of channels you want to acquire from, the channel considered for analog triggering is the first you put in the list.
Connect the error clusters whenever you can,in particular when you are dealing with I/O operations.
Bye!

How to display multi-channel image in the 'proxy'?

There're many examples to show how to display composite channels in the 'proxy'. But I don't find any example to show how to display multi-channel image in the 'proxy'. I found that I can use PSPixelOverlay to display alpha channel data like this:
int nSpotChannel = gChannelCount - 4;
PSPixelOverlay* overlay = new PSPixelOverlay[nSpotChannel];
for(int i = 0; i < nSpotChannel; i++){
       if( i != (nSpotChannel - 1) )
             overlay[i].next = overlay + i + 1;
       else
       overlay[i].next = NULL;
       overlay[i].data = gChannelData + (4 + i) * nPlaneBytes;
       overlay[i].rowBytes = gProxyRect.Width() * gDocDesc->depth / 8;
       overlay[i].colBytes = 1;
       overlay[i].r = 230;
       overlay[i].g = 161;
       overlay[i].b = 174;
       overlay[i].opacity = 255;
       overlay[i].overlayAlgorithm = kStandardAlphaOverlay;
pixels.pixelOverlays = overlay;
Then, Seeing red part, it will trigger a new problem, that is how to get the color value of the alpha channel by plung-in itself? It seems that no channel color value info is in FilterRecord.
If you have other solution, please tell me. Many thanks!

This is what I've been doing - was just curious if there was a way to see a more cohesive image.
If the individual EQ plugins are in fact the answer, is there any way to smooth how the Analyzer displays? The image I posted above, all of the tonal curves are very smooth. The analyzer tool shows a lot of peaks and valleys within the overall curve and it's hard to pinpoint each instrument's "sweet spot." Vocals for example are very hard to spot.
- Morgan

This is a very simple question about multi-channel audio playback

I have an mp4 file that i made and i made it 7.1 surround sound, and i'm pretty sure that this 7.1 surround sound works, as it can be played in VLC. i'm using netstream to load my files now. How do i make it so that flash can playback all 8-channels of sound? I suppose kglad would know the answer

Flash doesn't support multi-channel audio (yet?)

An application for multi-channel measurements

Does NI have a software solution for multi-channel measurements? I mean systems for measurements, tests and monitoring which contain numerous DAQ devices with thousands of sensors.
I suppose the software for such system should have the following features:
Instrument control
Sensor management (type, s/n, accuracy, calibration data, next calibration date, measurement limits, etc.)
Data acquisition
Storing data in databases
Data visualisation and analysis
Report generation
Tools for creating custom user interfaces / data visualisations for monitoring
As far as I know the DIAdem is great for data analysis, visualisation and report generation but it's not suitable for other tasks. With LabVIEW you can do anything but it's not an "out-of-the-box" solution.
Just to clarify what I'm talking about, here's an application that seems to fit the description. It's the HBM catman. Maybe someone worked with it? Do you know any analogues for it?

Just to add to Hooovahh's comments.
NI has flat out stated that they do not want to make turn-key solutions. That would take away from them being able to make tools for people to create the solutions. That is why they have alliance partners. These partners take the tools made by NI and make really cool stuff. My latest project was a software package that helped a technician build a jet engine correctly so that the turbine blades do not come out and destroy the engine (just slightly important). I have also done some test systems for space craft avionics.
So if you are really serious about this, I highly recommend finding an Alliance Partner to help you out. If you want, give me a PM and I can work on getting you and a few people on my side to discuss your requirements and proceed from there.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines

Channel Scan installation starts when TV is turned on

Toshiba 46UL605U LED TV - When you turn on the TV it always goes into channel scan (installation mode). Just started within the last month.
Is there a correction for this. What causes this

If you can't solve your issue and no one in the community can help, contact support to speak with a tech support agent at (800) 631-3811.
- Peter

Can PCM multi-channel wav (not DD or DTS) be sent over SPDIF

<Can PCM multi-channel wav (not DD or DTS) be sent over SPDIF? --- X-Fi Elite Pro SB055A and Audio Creation Mode ---
If I understand correctly, SPDIF format can support uncompressed MULTICHANNEL wav format (within the limitations of its bandwidth) as well as the more usual DD or DTS encoded format on SPDIF.
One of the neat things about Creative's Audio Creation Mode in the Recorder section is the ability to actually record to a multi-wav format (but the sample size seems to be fixed at 24 bit). This means it is quite simple to have several mixer inputs and record a mixed multi-channel wav file in one go. Great and this works as expected with a 5. ?24 bit/48 kHz recorded test file.
My question is when one plays this recorded multi-channel wav file back, the mixer monitor (playback) shows the various 5. (say) channels with their separate content. Can this multi-channel *uncompressed* wav data? be sent over the SPDIF output as is to preserve the PCM quality? (so no DD or DTS encoding used)? I have tried this and I?ONLY seem to be able to get a STEREO (2 channel mixed down) version received at another SPDIF-in sound card (my Audigy 2ZS PCMCIA). I tried almost all selections at both ends involving SPDIF.

@? In answer to my own question, and I think I had known this a while back, SPDIF standard only supports transmission of either 2 channel PCM (uncompressed) stereo with up to 24 bit resolution per channel and up to as much as 92 kHz sampling frequency, or compressed (DD or DTS) multichannel audio up to 5..
Since each frame of SPDF is 64 bits in length (with a single sample of L and R channels plus extra bits of status in each frame), at 92 kHz max sampling rate, this translates to about 3 Mbits/sec bit rate. However most SPDF don't support the 92 kHz rate (which for 24 bit would be the stereo rate for DVD-Audio) for various copyright protection reasons.
Here is short demonstration of SPDIF transmission of 24bit/96 kHz between two sound cards with and without "bit accurate for playback" enabled:
? http://www.jensign.com/spdif/

Multi-Channel (more than stereo) Audio Editing

Hi, is there a way of setting Audition, to when opening multi-channel WAVs, to open them all in one display?
Currently, if you open a stereo WAV, you get both channels visible so you can edit both channels as one.
However, if you open a 5.1 WAV, you get six separate mono WAV files listed.
This is a bit of a serious challenge to me as I'm trying to edit some surround SFX!

I'm afraid that currently, Audition is two channels per track max. I have no idea whether this will change in the future - a lot of other DAWs these days can certainly cope with more than two channels per track - I think Reaper does, for instance.

Multi-Channel output audio from Quick Time (or iTunes)

Hello all,
I am trying to get multi-channel AC3 audio output from QT and can only get two channel stereo. I have seen lots of related posts but can't quite get it.
I am trying to configure a Mac Mini to output properly via the TOS link port to my audio system. I get surround sound fine playing a DVD but not when playing a .m4v file that does give me surround sound when played on my Apple TV.
Should this be possible?

I appreciate the link Brent! I also had someone point me here http://fplanque.com/dev/mac/ac3-ac-3-5-1-surrond-sound-apple-mac-osx and all is good now.
Thanks!

AAC and multi-channel audio

Can AAC be used to encode multi-channel audio, such as DTS-HD Master Audio?
DTS-HD Master Audio is an optional audio format in Blu-Ray. It uses lossless compression.
There are other audio formats from Dolby Digital, for example, that are used to encode HD audio in Blu-Ray. Can AAC be used to encode those as well, without any loss of information?
Is there any work in progress to make HD audio such as DTS-HD Master Audio available discretely on disc, like what the older DVD-Audio format made possible for 5.1 channel surround sound on disc?
Thanks.

What adjustments do you want to make?

No multi-channel audio from DVD Player or Quicktime?

I have the A52Codec 1.7.6 installed. The codec preferences are set to output multi-channel audio. I have my Audio MIDI setup speaker configuration setup for multi-channel audio and the speaker assignment tests are all perfect. VLC plays back files with AC-3 soundtracks in perfect 5.1 multi-channel sound. Final Cut plays multi-channel audio properly as well.
When I watch a DVD, it is decoded to stereo. The dialog on 5.1 always comes from the left and right speakers and never from the center channel. It doesn't matter whether I remove the A52Codec and try again the result is aways the same, 5.1 audio in Quicktime and DVD Payer gets decoded to stereo. It is not that extra channels are missing, if that were true I'd get no dialog at all.
What do I have to do to make the DVD and Quicktime multi-channel audio decode as multi-channel audio and not stereo.

I'm not sure if this will resolve your issue or not, but have you configured it using /Utilities/Audi MIDI Setup ?

Multi Channel Input on Recei

http://img202.imageshack.us/img202/586/5pchinputlarge9cj.jpg[/img] width="300" alt="Image Hosted by ImageShack.us" >
Ok I know that for the front and rear I would use a 3.5mm stereo to RCA but for the center/sub channel what should I use? Should it be a 3.5mm mono to RCA or something different or can it be a regular stereo red and white one?
Btw how much does this degrade the quality of the sound? I hoping that this method with the multi channel inputs and nice home theater speakers sounds better than a PC speaker system like the 5500.

My setup is similar to yours.
- I have the 5. channel analog outputs of my X-Fi goes to the 5. multi-channel inputs of my preamp-processor. This setup alllow me not only to play my ripped music in 5. also allows me to play DVD-audio disc. You can also play DTS/DD encoded movies as well as long as you set the DD/DTS decoding option to off (internal decoding) in the creative console mixer.
Advantage: Can use the X-Fi CMSS-3D to get 5./7/ expansion
2- I also have the SPDIF output of the X-Fi goes to one digital coax input of my preamp-processor. This setup gives me the same processing as the above except the playback of DVD-audio disc.
Disadvantage: SPDIF will ouput only in stereo, you will need to use the receiver processing modes(Dolby prologic I/II, Neo6, Stereo 5/7) to get 5./7. expansion
For me connection 2 is the better choice for playback mode except DVD-audio, the reason is my preamp processor is a $4K unit with the highest (Audiophile) quality DACs, plus I have the flexibility of setting the bass-management of this unit independently. Plus, I have a multitude of processing modes on this unit such as : DPL-IIx, Neo-6, 5./7. Music etc... to expand a 2 channels signal into 5./7.
I can see you have a digital coax input on your receiver, just buy a mono 3.5mm to coaxial convertor. Connect the 3.5mm SPDIF end to the X-FI SPDIF flexi-jack, and the Coax digital end to your receiver Digital coax in. With this connection you need to set DD/DTS decoding on the X-Fi to ON (External decoder).
http://www.ramelectronics.net/html/RCA-mini-spdif.html#rcabncMessage Edited by BrokenOath on 2-8-2005 0:7 PM

How to building a multi-channels analog output task in visual c++ 6.0 (without Measurement Studio)?

Hello!
I have a PCI 6251 card, and using DAQmx C function to generate a wavwform. (single channel ).
But, how to creating a multi-channels analog output task, and had a different frequence in each channels?
Thanks.

This is getting to be a common question!
The answer is, you can't.
If the rates have common factors, you can use a higher overall rate. The slower waveform will simply have extra points in it to make up for the higher update rate.
John Weeks
WaveMetrics, Inc.
Phone (503) 620-3001
Fax (503) 620-6754
www.wavemetrics.com

Multi-channel Scan

Similar Messages

Maybe you are looking for