AWR1243: Sequencing of 3 frames

Hi,

Aren't we achieving that with txEnable = 0 ? Refer to chirp configurations 2 to 5 in our code snippet. txEnable is set to 0. Slave's chirp configurations 2 to 5 then employ different txEnable.

What about the LVDS valid signal? why we do not get it active during slave chirpping? We can still see on the spectrum analyzer that the device is employing all TX antennas.

Thanks

Hi,

any update on that?

Thanks.

Hello,

I don't get a full picture of your issue.

So you are saying that from Slave you don't get LVDS data? 

Do you observe spectrum with the device during the time when Tx off frame is running?

Regards,

Jitendra

Hi,

we want to make the following chirp configuration

MASTER TX0 -> SLAVE TX1 -> SLAVE TX2 -> MASTER TX0 ...

Meaning one chip at a time. We need 512 chirps per subframe. This is the solution we opted for:

if(deviceMap == 1U)

		{

			setChirpCfgArgs[0].chirpStartIdx = 0;

			setChirpCfgArgs[0].chirpEndIdx = 1;

			setChirpCfgArgs[0].profileId = 0;

			setChirpCfgArgs[0].startFreqVar = 0;

			setChirpCfgArgs[0].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[0].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[0].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[0].txEnable = 1U;



			setChirpCfgArgs[1].chirpStartIdx = 1;

			setChirpCfgArgs[1].chirpEndIdx = 2;

			setChirpCfgArgs[1].profileId = 0;

			setChirpCfgArgs[1].startFreqVar = 0;

			setChirpCfgArgs[1].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[1].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[1].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[1].txEnable = 1U;



			setChirpCfgArgs[2].chirpStartIdx = 2;

			setChirpCfgArgs[2].chirpEndIdx = 3;

			setChirpCfgArgs[2].profileId = 0;

			setChirpCfgArgs[2].startFreqVar = 0;

			setChirpCfgArgs[2].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[2].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[2].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[2].txEnable = 0U;



			setChirpCfgArgs[3].chirpStartIdx = 3;

			setChirpCfgArgs[3].chirpEndIdx = 4;

			setChirpCfgArgs[3].profileId = 0;

			setChirpCfgArgs[3].startFreqVar = 0;

			setChirpCfgArgs[3].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[3].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[3].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[3].txEnable = 0U;



			setChirpCfgArgs[4].chirpStartIdx = 4;

			setChirpCfgArgs[4].chirpEndIdx = 5;

			setChirpCfgArgs[4].profileId = 0;

			setChirpCfgArgs[4].startFreqVar = 0;

			setChirpCfgArgs[4].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[4].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[4].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[4].txEnable = 0U;



			setChirpCfgArgs[5].chirpStartIdx = 5;

			setChirpCfgArgs[5].chirpEndIdx = 6;

			setChirpCfgArgs[5].profileId = 0;

			setChirpCfgArgs[5].startFreqVar = 0;

			setChirpCfgArgs[5].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[5].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[5].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[5].txEnable = 0U;



		} else {



			setChirpCfgArgs[0].chirpStartIdx = 0;

			setChirpCfgArgs[0].chirpEndIdx = 1;

			setChirpCfgArgs[0].profileId = 0;

			setChirpCfgArgs[0].startFreqVar = 0;

			setChirpCfgArgs[0].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[0].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[0].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[0].txEnable = 0U;



			setChirpCfgArgs[1].chirpStartIdx = 1;

			setChirpCfgArgs[1].chirpEndIdx = 2;

			setChirpCfgArgs[1].profileId = 0;

			setChirpCfgArgs[1].startFreqVar = 0;

			setChirpCfgArgs[1].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[1].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[1].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[1].txEnable = 0U;



			setChirpCfgArgs[2].chirpStartIdx = 2;

			setChirpCfgArgs[2].chirpEndIdx = 3;

			setChirpCfgArgs[2].profileId = 0;

			setChirpCfgArgs[2].startFreqVar = 0;

			setChirpCfgArgs[2].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[2].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[2].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[2].txEnable = 2U;



			setChirpCfgArgs[3].chirpStartIdx = 3;

			setChirpCfgArgs[3].chirpEndIdx = 4;

			setChirpCfgArgs[3].profileId = 0;

			setChirpCfgArgs[3].startFreqVar = 0;

			setChirpCfgArgs[3].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[3].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[3].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[3].txEnable = 2U;



			setChirpCfgArgs[4].chirpStartIdx = 4;

			setChirpCfgArgs[4].chirpEndIdx = 5;

			setChirpCfgArgs[4].profileId = 0;

			setChirpCfgArgs[4].startFreqVar = 0;

			setChirpCfgArgs[4].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[4].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[4].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[4].txEnable = 4U;



			setChirpCfgArgs[5].chirpStartIdx = 5;

			setChirpCfgArgs[5].chirpEndIdx = 6;

			setChirpCfgArgs[5].profileId = 0;

			setChirpCfgArgs[5].startFreqVar = 0;

			setChirpCfgArgs[5].freqSlopeVar = freqSlopeVar;

			setChirpCfgArgs[5].idleTimeVar = idleTimeVar;

			setChirpCfgArgs[5].adcStartTimeVar = adcStartTimeVar;

			setChirpCfgArgs[5].txEnable = 4U;

		}

the reason two chirps are duplicated is because numLoops is limited to 255, so we could not find a better solution for that:

subFrameCfgArgs[0].forceProfileIdx = 0;

	subFrameCfgArgs[0].chirpStartIdx = 0;

	subFrameCfgArgs[0].numOfChirps = 2;

	subFrameCfgArgs[0].numLoops = 255;

	subFrameCfgArgs[0].burstPeriodicity = burstPeriodicity;

	subFrameCfgArgs[0].chirpStartIdxOffset = 0;

	subFrameCfgArgs[0].numOfBurst = 1;

	subFrameCfgArgs[0].numOfBurstLoops = 1;

	subFrameCfgArgs[0].subFramePeriodicity = subFramePeriodicity;



	subFrameDataCfgArgs[0].totalChirps = chirpEndIdx+1;

	subFrameDataCfgArgs[0].numChirpsInDataPacket = 1;



	subFrameCfgArgs[1].forceProfileIdx = 0;

	subFrameCfgArgs[1].chirpStartIdx = 2;

	subFrameCfgArgs[1].numOfChirps = 2;

	subFrameCfgArgs[1].numLoops = 255;

	subFrameCfgArgs[1].burstPeriodicity = burstPeriodicity;

	subFrameCfgArgs[1].chirpStartIdxOffset = 0;

	subFrameCfgArgs[1].numOfBurst = 1;

	subFrameCfgArgs[1].numOfBurstLoops = 1;

	subFrameCfgArgs[1].subFramePeriodicity = subFramePeriodicity;



	subFrameDataCfgArgs[1].totalChirps = chirpEndIdx+1;

	subFrameDataCfgArgs[1].numChirpsInDataPacket = 1;



	subFrameCfgArgs[2].forceProfileIdx = 0;

	subFrameCfgArgs[2].chirpStartIdx = 4;

	subFrameCfgArgs[2].numOfChirps = 2;

	subFrameCfgArgs[2].numLoops = 255;

	subFrameCfgArgs[2].burstPeriodicity = burstPeriodicity;

	subFrameCfgArgs[2].chirpStartIdxOffset = 0;

	subFrameCfgArgs[2].numOfBurst = 1;

	subFrameCfgArgs[2].numOfBurstLoops = 1;

	subFrameCfgArgs[2].subFramePeriodicity = subFramePeriodicity;

However, when checking LVDS valid (pin N4) on master we see a burst corresponding to subFrameCfgArgs[0], but not [1] or [2] which suggests to us that slave is not chirping.

Thanks.

Mario

Hi again,

going back to a more fundamental question: can we sequence 3 frames? or we have to rather use the advFrameConfig API methods to achieve the same results?

I recall we want to employ Master TX0 during a some chirps and then Slave TX1 during some other chirps (not simultaneously but sequentially).

Thanks

Hi,

any update on that?

Thanks

When you state this sentence - 'However, when checking LVDS valid (pin N4) on master we see a burst corresponding to subFrameCfgArgs[0], but not [1] or [2] which suggests to us that slave is not chirping.'

Did you check with SLAVE end the LVDS signal during subFrame?

And hopefully you are configuring subFrameCfgArgs[0-2] to both Master and slave but with different set of setChirpCfgArgs?

Regards,

Jitendra

Hi Jitendra,

we believe we have found the issue(s).

First of all, we believe we are not allowing for transfer time of CSI2/LVDS lanes. After some tunning of chirp duration and periodicities, we got more consistent LVDS valid signals.

On the other side, we want 512 chirps per sub-frame. For that, the workaround we found was to loop 255 times a unique chirp and repeat the burst twice -> 510. Then totalChirps must be set accordingly to get a proper LVDS signal. However we are not happy with that approach. I recall we want 512 chirps using one TX antenna, 512 using another TX antenna and finally 512 chirps using the third available antenna. For this we have to define at least 3 unique chirps if I'm not mistaken.

Any suggestions on how to get to 512 (instead of 510)?

Thanks

Great, thanks for your support!