DCA1000EVM: Synchronized Frame Triggering issue

Hello Ahmad,

At what point are you feeding the pulse on the AWR1642BOOST? From the point of input is there connection all the way to the AWR device pin? ie, can you verify if there is any series resistor not present in the path?

The pulse width need not be so much, 1 msec or so is more than enough. you need to click on "Trigger frame" and then provide the pulse input. Are you providing only a single pulse or is the pulse continuously ongoing? I would suggest you keep the pulse continuously running, with periodicity set to 41msec (slightly more that the programmed frame periodicity above) .

regards,

Vivek

Hi Vivek,

Both the Arduino and the AWR1642BOOST are powered on at the same time, then the pulse train starts after the AWR1642BOOST is initialized and the "Trigger Frame" button is hit.

The signal from the output pin of the Arduino is fed directly to the SYNC_IN pin in the AWR1642BOOST board with no resistors or any other circuit components in between.

All of this, BTY, happens while the AWR1642BOOST is connected to the DCA1000 to capture the data.

Please see the picture below as I changed the SYNC_IN signal from a single pulse to pulse train as advice in the previous response.

However, the radar is still not triggered in the "HardwareTrigger" mode.

Thanks.

Hello,

Can you check on your EVM if the resister R165, which connects the pin 9 of the J6 connector to the AWR device pin , is assembled? Which revision of the AWR1642BOOST do you have? Rev A or Rev B? It would be printed on the EVM.

Regards,

vivek

The J6 20-pin LaunchPad connector as a whole is directly attached to the EVM and I kept all the connections on the EVM as is. Could you please provide me more details about the location of the R165 resistor as I couldn't locate on the EVM nor find any information about it in the data sheet.

I am using AWR1642BOOST rev B but I also have rev A that I can use if that would provide an easier solution.

Thanks.

Hello Ahmad,

You can find the assembly files in the following file:

The Rev B should have R165 installed by default, but you can double check that. There is another issue, the SYCN IN pin is also connected to the DCA1000 via R62. So the DCA1000 would also be driving this pin. You need to remove the R62 so that there are not two drivers on the SYNC IN pin.

Regards,
Vivek

Hi Vivek,

So I took off the R62 resistor and made sure the R165 resistor is there. Now the Radar works in the "HardwareTriggering" mode but it doesn't use the SYNC_IN signal given by the Arduino.

In other words, whenever I press the triggering button the data are taken directly without waiting for the SYNC_IN signal to be fed.

Thank you.

Hello Ahmad,

The signal needs to be low before you start frames. If its high by default it would detect is as a trigger.

Regards,

Vivek

Hi Vivek,

I made sure of that and it still happens.

I even disconnected the Arduino output from the SYNC_IN pin and still the frames are triggered once I hit the triggering button.

In other word, changing the triggering mode now is not making any difference.

Thank you.

Hello Ahmad,

How many frames are you triggering and are all the frames been sent out or only the first frame? In HW triggered mode the frames cannot get triggered unless the devices sees a high level on the SYCN IN pin. Can you probe the SYNC IN signal close of the AWR1642 pin and check the level? Disconnecting it from Ardrino does not guarantee the signal is low, it needs to be driven low

Regards,
Vivek

Hi Vivek,

I am setting it to send 8 frames and it was all sent out.

However, the ver B EVM is working great now. Your last set of instructions was perfect but it didn't work out for me before because I didn't do proper grounding (the two circuits didn't have a common ground!).

Thank you so much for your help.

Before I close this thread, I have another EVM which is ver A. What modifications should I make on it to be able to use it with the SYNC_IN feature?

Best.

Hello Ahmad,

Glad to hear that you are able to get the SYNC IN working now.

In Rev A the changes are the same, only additional change is you might need to mount R165 also which is not installed on Rev A by default.

Regards,

vivek

Hi Vivek,

What specs does the R165 has to meet? (type, value, etc.)

Thanks.