AWR1243: Frame Periodicity calculation

Hi,
Could you explain the reason why are your seeking to obtain 100% frame duty cycle?
As Host requires Inter-frame idle time to do the FFT processing (2-D, 3-D etc.) after collecting Raw-ADC data for all the chirps (and do the 1-D FFT during inter-chirp duration).


Regards,
Jitendra

Hi

The FFT processing is done outside of the AWR1243 chip, I only intend to collect RAW-ADC data. Having said that, I need to minimize the inter-chirp time as much as possible to fully utilize the AWR1243.

This is my use case. 

Given N different waveform configurations ( chirp/profile/frame configurations), Let's say its' N = 2

waveform 1 = 1ms total chirp time, 1ms inter frame time, -> 2 ms frame periodicity 

waveform 2 = 2ms total chirp time, 2ms inter frame time, -> 4 ms frame periodicity 

In 12ms I can have 2 x waveform1 + 2x waveform2 -> 4ms + 8ms

However, if the inter frame time is 0 ms, I can fired off 4 x waveform1 + 4x waveform2 -> 4ms + 8ms

 

Thanks, 

Dom

Hi, 

I understand the inter-frame time must be >=200us. However, when the following parameters were program,

chirpCfg.chirpStartIdx	0
chirpCfg.chirpEndIdx	3
chirpCfg.profileId	0
chirpCfg.startFreqVar	0
chirpCfg.freqSlopeVar	0
chirpCfg.idleTimeVar	0
chirpCfg.adcStartTimeVar	0
chirpCfg.txEnable	5
frameCfg.chirpStartIdx	0
frameCfg.chirpEndIdx	3
frameCfg.numLoops	128
frameCfg.numFrames	1
frameCfg.numAdcSamples	750
frameCfg.framePeriodicity	3040000
frameCfg.triggerSelect	2
frameCfg.frameTriggerDelay	0
profileCfg.profileId	0
profileCfg.pfVcoSelect	0
profileCfg.pfCalLutUpdate	0
profileCfg.startFreqConst	1435388860
profileCfg.idleTimeConst	300
profileCfg.adcStartTimeConst	440
profileCfg.rampEndTime	2540
profileCfg.txOutPowerBackoffCode	0
profileCfg.txPhaseShifter	0
profileCfg.freqSlopeConst	181
profileCfg.txStartTime	0
profileCfg.numAdcSamples	375
profileCfg.digOutSampleRate	18750
profileCfg.hpfCornerFreq1	0
profileCfg.hpfCornerFreq2	0
profileCfg.rxGain	48

The AWR will generate the error below once multiple frames of the above setting were trigger

Sub block 0x1011 – AWR_CAL_MON_TIMING_FAIL_REPORT_AE_SB

Error code : 0x5

This is unexpected because all the one time & periodic calibration of various RF/analog aspects are disabled by calling rlRfRunTimeCalibConfig with arlRunTimeCalibConf_t = {0}. Moreover, if the frame periodicity is modify from 3040000 to 3240000. The timing fail report error will go away. 

Hi,
Don't call rlRfRunTimeCalibConfig API, even though you disable all the calib option, there are few default calibrations device does at the invocation of this API.

Hopefully, without this API call, you should able to achieve your frame/chirp timing constraint.


Regards,
Jitendra

Hi,

I tried to not call rlRfRunTimeCalibConfig API config and I am still unable to achieve my frame/chirp timing constraint.

The setting I posted on Oct 22, 2018 5:21 PM had an overhead of 659,200ns = framePeriodicity - frameTime = (3040000 * 5ns) - ((2540 + 300) * 10ns * 512 chirps) = 15,200,000ns - 14,540,800ns. which already far exceeded the 200us specified in the ICD. Having said that, how should framePeriodicity be derived?

Thanks,
Dom

Hi Dom,
Could you try running same scenario with DCA1000 and AWR1243 using mmWve-Studio to verify this config? Configuration and timing wise it looks, having said that this is unusual case where frame is loaded ~95% duty cycle with HSI (LVDS/CSI-2) data being pump out.
And when are you saying you are not able to achieve timing constraint, that means device is throwing an error while capturing data with this configuration?
You have correctly derived Frameperiodicity which is based on [(chirp-ramp-time+chirp-idle-time)*(chirp-end-idx - chirp-start-idx + 1)* numOfLoop + idle-frame-time]

Are you using CSI-2 or LVDS to read the raw data at External Host? Make sure that these interface is running sufficient data rate which should enough to capture chirp data during one chirp end time to start of next chirp.


Regards,
Jitendra

Hi Jitendra,

Could you try running same scenario with DCA1000 and AWR1243 using mmWve-Studio to verify this config?
No, I don't have access to DCA1000, therefore I won't be able to verify this configuration as you suggested.

And when are you saying you are not able to achieve timing constraint, that means device is throwing an error while capturing data with this configuration?
Yes, the device is throwing the AWR_CAL_MON_TIMING_FAIL_REPORT_AE_SB (error code 0x5) with this configuration.

Are you using CSI-2 or LVDS to read the raw data at External Host?
I am using LVDS to read the raw data t external host.

Back to my original question, how come the AWR1243 is throwing the AWR_CAL_MON_TIMING_FAIL_REPORT_AE_SB error even though the framePeriodicity is program to meet the requirement specified in the ICD. If possible, can you try the same settings on your end to recreate the problem?


framePeriodicity 3040000
profileCfg.idleTimeConst 300
profileCfg.rampEndTime 2540
frameCfg.chirpStartIdx 0
frameCfg.chirpEndIdx 3
frameCfg.numLoops 128


Thanks,

Dom