Converting digital waveform into bit sequence

Dear friends,
I am stuck with the task of converting a digital waveform (16 bit values) into
the following waveform:
each sample of the original waveform should be represented by a sequence of
bits (or H and L analog values) in the second waveform,
the duration of the bit sequence should be half (in general arbitrary fraction)
of the sample clock period of the original waveform,
the bit sequence should be padded by zeros so that the total duration of the
bit sequence and the pad equals to the sample clock period of the first
waveform.
I tried to represent these two waveforms in the picture attached.
It would be really great if someone could give me hints/suggestions to this
problem!
Thanks in advance!
Attachments:
waveforms.JPG ‏21 KB

Hi SamboNI,
Thanks for your reply!
I have couple of notes:
I tried to implement your instructions but the LabView gives error message
(please see the screenshot attached).
I guess there should be "Boolean to (1,0)" VI between "Number to
Boolean Array" and "Build Array" VIs (?)
The problem I have is a bit more complex:
I have a digital waveform (16 bit integers). I need to transform the waveform
in the easiest and fastest way into the following form:
Each sample of the original waveform (16 bit integer number, i.e. 5) should be
represented by a sequence of 0s and 1s corresponding to the bit sequence of that number (0000000000000101 for 5) padded
by a sequence of zeros (i.e. 00000) in the final waveform. I will use the
final waveform to drive single line of the 6534 board instead of 16 lines of
this bopard in the case of the original waveform.
More generally:
I need to realize communication protocol with the AD5541
Digital-to Analog converter from Analog Devices (
http://www.analog.com/en/prod/0%2C2877%2CAD5541%2C00.html ) using 6534 NI
board. Therefore I need also build SCLK and CS waveforms and synchronize
them with the DATA waveform I was talking above. Is there a way to do this?
By the way - do LabView have standard means to communicate
with devices like AD5541? Does it require a special software module and/or
hardware board?
Thanks in advance!
Attachments:
NumToBoolErr.JPG ‏16 KB

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Convert digital waveform to array

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Example_VI_BD.png ‏11 KB

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shubham62 wrote:
We are implimenting real time audio trans-receiver. We have converted input audio data(analog form) into digital data. At the receiver side we received digital data which is in the form of digital data array.But we are unable to recover back our original input data. So please help us to sort out the problem.
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Message Edited by GerdW on 01-28-2008 09:23 AM
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Thanks for the replies.
In response to John's points:
1. The attached VI is a simplification of an FPGA VI that read a fixed number of samples from a DMA FIFO using an FPGA Interface Invoke Method approach. I'm using a card (PXI-7842R) that doesn't allow use of the Acquire Read Region method. In order to allow people without an FPGA card to hopefully see the issue, I replaced it with the for loop. Assuming that this for loop does leak (which I don't believe it does; as altenbach said, it's a fixed size allocation that LV should be able to reuse), why would I see a difference in the leak magnitude depending on which indicator I connect to the array?
2. I've previously reviewed the document you referenced, and I don't see any errors from it present in my code; do you? I have no global/local variables, strings/arrays displayed on front panel, property nodes, coercion dots, altered memory sizes, resizing/reallocations, etc. I don't see any weird buffer allocations. I used to have the conversion from U16 array to digital waveforms in a subVI but placed it on the same diagram to allow incremental use of the Diagram Disable structure.
3. The forum post you referenced had many of the items discussed above, plus it was solved using an RT FIFO. I'm not passing data from a producer to a consumer; I'm just displaying acquisition results. I guess you could say I'm processing the data, but I'm really only converting it to a format that the indicator will take; I'm not operating on the data.
It's good that the leak doesn't show up in 2014, but my SSP runs out in a couple of days; I never got an upgrade to 2014. This is the last item remaining on the development path, and we've already spent ~$4k to upgrade the controllers enough to display the acquisition without dragging down the CPU. I will be in hot water if I spent all that money and then end up having to scrap the display...

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Message Edited by Troy K on 03-23-2008 11:37 AM
Troy
CLDEach snowflake in an avalanche pleads not guilty. - Stanislaw J. Lec
I haven't failed, I've found 10,000 ways that don't work - Thomas Edison
Beware of the man who won't be bothered with details. - William Feather
The greatest of faults is to be conscious of none. - Thomas Carlyle
Attachments:
array_to_digital1.png ‏4 KB
array_to_digital.png ‏9 KB

Converting digital waveform into bit sequence

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