Hi Everyone ,
I am using ad9364 and zynq zc702 and non os software . I would like to know how can I test the received samples in a spectrum analyzer in case I am using windows operating system.
Thanks & Regards
In you configuration the transmit path is set to 2450 MHz while the receive path is set to 2400 MHz. So what you are receiving is not what you are transmitting but probably some other signals from you environment.
Using the IIO Scope with your custom bitstream shouldn't be an issue.
I'm not sure what you are asking.
Tx -> spectrum analyzer?
Rx -> FFT
If it's the 2nd - use Linux, that is what we developed it for.
Hi rgetz ,
Thanks for replying . You are right , I am asking Rx - FFT . Actually I am trying to integrate a HDL block for QPSK modem at the transmitter side . I think if I I remove the axi_ad9361_dac_dma and integrate my custom HDL code ,which will stream the samples to util_dac_unpack when dma_rd will go high , then it should work fine. I want to check the spectrum on the received side . Can I do the same thing by using the OS mode ?
What you are trying to do seems to be correct.
For an example of how to download the captured samples on a PC, take a look at the capture script (no-OS/ad9361/scripts/zc702 at master · analogdevicesinc/no-OS · GitHub). On the no-OS software, if you will define the CAPTURE_SCRIPT symbol, 16384 samples will be captured and stored in memory starting from ADC_DDR_BASEADDR address (no-OS/main.c at master · analogdevicesinc/no-OS · GitHub).
Hi Dragos & regetz,
Thanks for replying ,I was thinking if i change the .bit file by including my custom HDL code and build a boot images with the steps using http://wiki.analog.com/resources/eval/user-guides/ad-fmcomms2-ebz/software/linux/zynq and load linux in Zynq then I must be able to use IIO scope as well . Is that correct ?
Hi Dragos ,
I tried to load Linux and see the wave forms with default settings on IIO scope . I am attaching the snapshots of the waveform and the parameters .
are the wave forms correct ? why is there so many spikes at different frequencies when I am sending a One CW tone at a frequency of 10 Mhz.
I had another question . Is it possible for me to create a bit file with my custom design and make boot images from that and use IIO scope for my custom changes? .
Thanks for the reply , I have two more questions
1.) I have integrated my custom HDL code with the default setup by bypassing the DMA . I am sending the same sine wave samples from a look up table in HDL . I saw the spectrum as well in spectrum analyzer . I am getting peak at 960 Khz . Is the frequency correct ? (Is it 30.72 Mhz * 1/32 i.e sample rate * cycle /sample)?
2.)I want to perform QPSK on the sine wave samples , I read in another thread that the format in which the I Q samples of sine wave are trasmitted is the following
"At this clock, the dac input data will appear like this-
I0 = 0
I1 = 49
I2 = 97
I3 = 141
Q0 = 255
Q1 = 250
Q2 = 236
Q3 = 212
Is the format same for ad9364 ?
1) The output frequency you'll get depends on the size of your lookup table. If you have one full sine-wave cylce from 0 to 2pi in your look-up table and you output one sample from the LUT for each ADC sample the output frequency will be (ADC sampling frequency) / (LUT size). So if your LUT size is 32 and your ADC sample frequency is 30.72 MHz you should see a peak at 960 kHz.
2) The AD9364 core takes in a 64-bit word, where the layout is 16-bit I1, 16-bit Q1, 16-bit I2, 16-bit Q2.
Thanks , that was very helpful . I have implemented the transmitter. At each dma_rd signal I am generating 2 samples . I have kept "two_rx_two_tx_mode_enable" as 0 in the main.c .
At the receiver side I want to implement the demodulator in HDL and place it before the DMA . I see at each util_adc_pack_dsynch/valid there are two samples . Can you please elaborate the receiver path set up btw util_adc_pack and dma
I'm not sure if I understand the question.
If you want to add a de-modulator into the HDL you can add this demodulator between the axi_ad9361_if core and the util_adc_pack core.
Hi Larc ,
Thanks for your reply . I have now done what you suggested. Thanks again .
Retrieving data ...