- 3rd March 2008, 10:14 #1

- Join Date
- Dec 2007
- Location
- Chennai,India
- Posts
- 466
- Helped
- 56 / 56
- Points
- 3,665
- Level
- 14

## chipscope bus plot

I have a program for FPGA which sends 14-bit sine values to dac. I want to check the sine wave using chipscope's Bus plot. I'm able to see the IO lines output in Chipscop,but I can't really find anything about using bus plot it....If any experts ever have used it to plot the data wrt time,please help me.Also tell me if it's possible to plot the sine wave from the DAC values?....Thanks

- 3rd March 2008, 12:05 #2

- Join Date
- Jul 2007
- Posts
- 100
- Helped
- 5 / 5
- Points
- 1,397
- Level
- 8

## chipscope export waveform

answering to point -2(Also tell me if it's possible to plot the sine wave from the DAC values?) yes its possible tap input to dac & export to an output file and just use matlab to plot it .

- 3rd March 2008, 12:05

- 4th March 2008, 04:37 #3

- Join Date
- Dec 2007
- Location
- Chennai,India
- Posts
- 466
- Helped
- 56 / 56
- Points
- 3,665
- Level
- 14

## capturing data with chipscope matlab

yes its possible tap input to dac & export to an output file and just use matlab to plot it .

- 4th March 2008, 04:37

- 4th March 2008, 05:43 #4

- Join Date
- Jul 2007
- Posts
- 100
- Helped
- 5 / 5
- Points
- 1,397
- Level
- 8

## how to check clock frequency using chipscope

Added after 15 minutes:

[quote="real time data"]

even if you plot the data using chipscope the plot is on some fixed set of samples collected from a buffer of size you have choosen . so you can go by this way that you export the data of output waveform(file -> export command in c-scope) in unsigned or signed format into an output file as per requirment and just plot it in mlab

- 4th March 2008, 05:43

- 4th March 2008, 10:39 #5

- Join Date
- Dec 2007
- Location
- Chennai,India
- Posts
- 466
- Helped
- 56 / 56
- Points
- 3,665
- Level
- 14

## export chipscope waveforms

Thanks! ya...I will see for it and post the results as soon as possible....

Added after 54 minutes:

Hi!, I tried like you have said...But in export option,it only gives three format (.vcd,.asc,.fbdh)....How can you export the file to Matlab format?...Please help!....I'm using chipscope 8.2 with xilinx 8.2i

- 5th March 2008, 02:58 #6

- Join Date
- Jul 2007
- Posts
- 100
- Helped
- 5 / 5
- Points
- 1,397
- Level
- 8

## export chipscope waveform

After you capture the waveform you change it to signed values and export it as ascii format . Now the exported file will have the signed values of wave form .This file you load it in mlab

- 5th March 2008, 04:31 #7

- Join Date
- Dec 2007
- Location
- Chennai,India
- Posts
- 466
- Helped
- 56 / 56
- Points
- 3,665
- Level
- 14

## matlab +chipscope

Yes, I did! already export using ascii format....The big issue is that I get the same waveform in chipscope,matlab and in excel. All waveforms don't look like a sine but having series of ups and downs....Samples are not correctly placed....But when I connect the CRO to dac, I get a pure sinewave at 2MHz. can the chipscope really capture\plot the data at such high speeds?....Have you ever done that before?......

- 5th March 2008, 05:57 #8

- Join Date
- Jul 2007
- Posts
- 100
- Helped
- 5 / 5
- Points
- 1,397
- Level
- 8

## chipscope how to exprot data

For sampling a 2 MHz sine wave hardly 4 MHz clock rate is sufficient .The problem is not with the c-scope . Is the sine wave is a generated one inside fpga (I mean have you hard-coded the values and than reading) .Can u paste the output wave which is wrong

- 5th March 2008, 09:46 #9

- Join Date
- Dec 2007
- Location
- Chennai,India
- Posts
- 466
- Helped
- 56 / 56
- Points
- 3,665
- Level
- 14

## chipscope export to matlab

Hey guys!, I have got the sine wave exactly as I expected....All you need to do is to first select your individual data pins and then add them to a new bus. Name it as you like. Then highlight it by clicking it. Now click the Bus Plot on the top left(double click). By clicking run button, you will be able to get some waveform. Now it won't look like a sine after all...Last correction is that you have to select "Reverse bus" option by right clicking the new bus created...Now no wonder if you get sine wave"...

To Kalyansrinivas,

It's so simple and easy step Kalyansrinivas.....I tried the ways as you have said...Now I'm able to plot the wave in matlab too...However it doesn't add the convinient of plotting the data in realtime as Chipscope does.!!!.Also capturing and plotting the wave doesn't really make any sense with frequency,because though at first I changed the frequency of my dac clock,I couldn't get any results familiar....All you need to do is to select "Reverse Bus option"Anyway thanks friend!...