CCS/AWR1642BOOST: AWR1642: How to read 1dfft data from Ti in mmw demo

Hi

In dss_main.c:: MmwDemo_dssSendProcessOutputToMSS, you can add an extra message to send the 1D FFT output through UART.  The 1D FFT output for one whole frame is stored in the variable radarCube.

You can modify the code corresponding to the rangeDopplerHeatMap to send the radarCube out.

if (pGuiMonSel->rangeDopplerHeatMap == 1)

{

   itemPayloadLen = obj->numRangeBins * obj->numDopplerBins * sizeof(uint16_t);

   message.body.detObj.tlv[tlvIdx].length = itemPayloadLen;

   message.body.detObj.tlv[tlvIdx].type = MMWDEMO_OUTPUT_MSG_RANGE_DOPPLER_HEAT_MAP;

   message.body.detObj.tlv[tlvIdx].address = (uint32_t) obj->detMatrix;

   tlvIdx++;

   totalPacketLen += sizeof(MmwDemo_output_message_tl) + itemPayloadLen;

}

ff you modify the above code as follows, it will send the radarCube instead of the rangedoppler heat map

if (1)

{

   itemPayloadLen = obj->numVirtualAntAzim* obj->numRangeBins * obj->numDopplerBins * sizeof(uint16_t)*2;

   message.body.detObj.tlv[tlvIdx].length = itemPayloadLen;

   message.body.detObj.tlv[tlvIdx].type = MMWDEMO_OUTPUT_MSG_RANGE_DOPPLER_HEAT_MAP;

   message.body.detObj.tlv[tlvIdx].address = (uint32_t) obj->radarCube;

   tlvIdx++;

   totalPacketLen += sizeof(MmwDemo_output_message_tl) + itemPayloadLen;

}

 

Set your frame rate to something small 0.25 Hz, since it would take a long time to transfer the 1D FFT output for a single frame

Regards

Anil

Hi, 

No. It cannot be seen in the visualizer. You'd have to write your own visualizer to view the data. 

Regards

Anil

Hi Taiga,

Apologies. I just realized that the slowest framerate is ~1Hz, and it seems as though the UART data rate isn't sufficient to transfer the radarcube in 1Hz. Could you share the exact error you are seeing when you set the frame rate to 1Hz?

My suggestion would be to reduce the size of the radarcube.

Could you try again with the 64 ADC samples per chirp, and only 16 chirps?  You could try the following configuration.

sensorStop

flushCfg

dfeDataOutputMode 1

channelCfg 15 3 0

adcCfg 2 1

adcbufCfg -1 0 0 1 0

profileCfg 0 77 7 7 58 0 0  68 1 64 5500 0 0 30

chirpCfg 0 0 0 0 0 0 0 1

frameCfg 0 0 16 0 1000 1 0

lowPower 0 0

guiMonitor -1 1 1 1 1 1 1

cfarCfg -1 0 2 8 4 4 0 5120

cfarCfg -1 1 0 8 4 4 0 5120

peakGrouping -1 1 0 0 1 224

multiObjBeamForming -1 1 0.5

calibDcRangeSig -1 0 -5 8 256

extendedMaxVelocity -1 0

clutterRemoval -1 0

compRangeBiasAndRxChanPhase 0.0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0

measureRangeBiasAndRxChanPhase 0 1.5 0.2

sensorStart

 

Regards

Anil

Hi Taiga,

The UART interface can transfer data at speeds of up to 921600 bps (or ~100kilobytes/sec). In practice, and with overheads, we can manage about 50kilobytes/sec

The size of the radar cube is 64 x 16 x 4 x 4 bytes (16kilobytes). Where
1. Length of 1D FFT output per chirp- 64
2. Number of Chirps per frame - 16
3. Number of Rx enabled - 4
4. Bytes per ADC sample - 4 (Each ADC sample is a complex number with 2 bytes for the real part and 2 for the imaginary part).

The radarcube that is to be transferred out is 16kilobytes/sec.

Note that in addition to the radarCube the device also sends out detected objects, some profiling information, the range profile, and some header information. The total packet size per frame should be less than the rate which is why we've selected such a small size.

Regards
Anil