AWR1843: How ADC Data stored in such configuration?

Ruifeng Du

Part Number: AWR1843

Hi:

I use AWR1843 Demo project, found that ADC Buf configured like this:

   dataFormat.adcOutFormat = 0;
    dataFormat.channelInterleave = 1;/* Sample Interleave must be I(MSB) Q(LSB) for HWA usage. */
    dataFormat.sampleInterleave = 1;

But I found that AWR1843 is litter endian, channelInterleave = 1 means that ADC data stroed in memory frome low should like:

in each data Q(imag part) data should be at low address, and I(real part) should be at high address, like:

Rx0(3)_Q/Rx0(3)_I Rx0(2)_Q/Rx0(2)_I Rx0(1)_Q/Rx(1)_I Rx0(0)_Q/Rx0(0)_I

But HWA needs I(real part) at low address, and Q(imag part) at high address,

the configure seems not match HWA input.

over 4 years ago

0 Ruifeng Du over 4 years ago

Prodigy 20 points

I make some test data to test hwa, found that fft operation in hwa, for every 32-bit data, seems treat low address as imag part(Q), and high address as real part(I), which is different with hwa datasheet

0 Aniket Mahajan over 4 years ago in reply to Ruifeng Du

TI__Genius 15046 points

Hi,

Let me consult the documentation and get back to you by tomorrow.

Regards,

Aayush

0 Jitendra Gupta over 4 years ago in reply to Ruifeng Du

TI__Guru 69960 points

Hi,

Please refer this app-note explaining non-interleaved data format

https://www.ti.com/lit/an/swra555a/swra555a.pdf (figure 4)

And for HWA, I would recommend you to refer mmw demo which uses HWA for data processing (DPC objectdetection C:\ti\mmwave_sdk_03_05_00_04\packages\ti\datapath\dpc\objectdetection) where it has all the data copy from ADC-Buffer to HWA memory in right manner to get the processing done by HWA.

Regards,

Jitendra

0 Ruifeng Du over 4 years ago in reply to Jitendra Gupta

Prodigy 20 points

Jitendra Gupta said:
processing

Hi:

I checked the

genChirpData() function in DPC objectdetection, the ADC Raw data generated as struct cmplx16ImRe_t.
and send directly to HWA, but I think HWA should process data which has struct like cmplx16ReIm_t
referred to hwa user guide, and the screenshot above,
because hwa treat LSB as I(real part) and MSB as Q(imag part)

Regards.

0 Jitendra Gupta over 4 years ago in reply to Ruifeng Du

TI__Guru 69960 points

Are you facing any problem in your application? or is it just documentation mismatch you are referring?

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AWR1843: How ADC Data stored in such configuration?