data acquisition FPGA LX9 and OPENADC


#1

Hello .I only wish to acquire data, I do not want to do any processing on FPGA. I want to acquire data in csv file (excel) frequency of 4 MHz (+ - 500 mV),
I got the OpenADC, FPGA Avnet LX9, Shielded magnetic field probe AND preanplificador , really enjoy the LNA.
I am following the guide below:
assembla.com/spaces/openadc … tart_Guide.

to program the FPGA, have I to buy the flash digilentinc.com/Products/Detail … =SFUTILITY ?

that is program_ flash.bat AND SFUtility?? :unamused: :unamused:

Thank…


#2

Hello,

You don’t need to buy anything actually! The LX9 board has the programmer built into it… it uses SFUtility which is the “Download” button on the page you linked to. If it doesn’t work the direct link is here: digilentinc.com/Data/Produc … sfutil.zip

Let me know if it works. I’m on the road so can’t duplicate your hardware to test unfortunately, but it should still work as described before.

-Colin


#3

Hey, watch your video:
youtube.com/watch?v=YY6F8VC … outube.com
The sampling frequency with which you use is 40 Mhz, you could increase it to 100 MHz or more? What is the limit?
considering that the Openadc AD9215 sample rate is 105 Mhz. :confused:
where in the code you can change the sampling rate Whereas OpenADC USB port with AT90USB162(FPGA LX9) has a maximum rate is 12Mbps. :cry: .
I have the electromagnetic probe, I want to measure the magnetic field of a chip.
I have read the signal on an oscilloscope, and the signal is greater than 100 MHz, as I can read it if OpenADC limited to 105 Mhz. :astonished: :astonished:


#4

Hi Edward,

Have been on the road so a lot slower on responses. For the OpenADC frequency, it’s set as part of the FPGA code described at assembla.com/spaces/openadc … tart_Guide .

The data is always stored to an internal memory on the FPGA. Thus the 12 Mbps isn’t a big deal, as it captures ~30k samples to memory than downloads that over the serial-USB port. Something like the CHipWHisperer-Lite has a faster USB interface, but is still limited to capture/download (i.e. does not live stream).

Hope this helps!

-Colin


#5

The data is always stored to an internal memory on the FPGA. THUS the 12 Mbps is not a big deal, as it captures ~ 30k samples to memory than That downloads over the serial-USB port.
wilt say for the USB port are data every 30 k ?, python travel data to 30k each shipment?
These 30k can be changed?
you use the entire memory capacity of 64 MB LX9 LPDDR SDRAM?


#6

The DDR code wasn’t fully implemented… I think it was used at one point, but it might take some work to get it working with the latest FPGA code. Right now it’s basically limited to around 30k samples, due to the size of the FPGA.


#7

Dear Colin making changes to the qt , scan and openadc files but these changes are not saved because no change was shown when I run in program.
How can I do to make changes in the QT files, and scan openadc ???
each time a change is made in these files I need to reinstall install_win.Bat ??
:confused: :confused:


#8

Hello,

Where are you modifying the .py files? Wherever you ran the original “python setup.py develop” from needs to be the location. You can also check if Python prints a little message telling you the location of the files it’s running from.

You shouldn’t need to do anything beyond save the file to have it pulled in. But it’s possible during the install process it was copied elsewhere, so isn’t running your copy.

-Colin