IWR6843AOPEVM: IWR6843AOPEVM

Part Number: IWR6843AOPEVM
Other Parts Discussed in Thread: IWR6843ISK, IWR6843AOP, MMWAVE-STUDIO, MMWAVEICBOOST

Tool/software:

I am looking to trigger the frame capture of the IWR6843AOPEVM as I have seen several people have successfully done that.

For instance, [with IWR6843AOPEVM here](https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1231464/iwr6843aopevm-hardware-triggering-sync_in-pulse-requirements)

and [with IWR6843ISK here](https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1039687/mmwaveicboost-mmwave-studio-calling_connecttarget-returned-3-error)

and [with IWR6843ISK again](https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/972613/iwr6843isk-hardware-trigger ).

I have gone through these discussions, the relevant SDK link, and the schematics for IWR6843AOP. 

But I still have some upfront questions.

1. where is the SYNC_IN pin on IWR6843AOPEVM if it exists? Do I need a DCA boost carrier board for sync?

2. I have seen some post about replacing resistors from the DCA carrier board for sync, I guess we don't need to do that for IWR6843AOPEVM, right?

3. We need 3.3V PWM signals to SYNC_IN, right?

Thank you for your clarification,

  • Hi Josh,

    1. where is the SYNC_IN pin on IWR6843AOPEVM if it exists? Do I need a DCA boost carrier board for sync?

    The IWR6843AOPEVM does not have a SYNC_IN in pin or test point. The SYNC_IN signal is routed to DCA1000 board or MMWAVEICBOOST board to provide hardware trigger using the MMWAVE-STUDIO software. Either you may use DCA1000 or ICBOOST board along with IWR6843AOPEVM to provide SYNC_IN using MMWAVE STUDIO software (OR) you will need to tap in the SYNC_IN signal at RA8A or R157 to blue wire and provide hardware trigger externally using a signal generator. 

    In case, you are using STUDIO software, trigger select should be Hardware instead of software, see below.

    2. I have seen some post about replacing resistors from the DCA carrier board for sync, I guess we don't need to do that for IWR6843AOPEVM, right?

    As explained above, if you wish to tap in the SYNC_IN signal at RA8A or R157 to blue wire and provide hardware trigger externally using a signal generator you will not need DCA1000 board. DCA1000 board would be feasible to provide HW_TRIGGER without any additional blue wiring.

    3. We need 3.3V PWM signals to SYNC_IN, right?

    Yes, we will need 3.3V PWM signal to provide HW trigger to SYNC_IN. Below are few additional timing requirements that needs to be followed.

    Regards

    Ankit

  • Hi Ankit, Thank you for the prompt response.

    Yes. For the 3 options mentioned by you, I am familiar with

    a. DCA1000(https://www.ti.com/tool/DCA1000EVM),

    first time to know

    b. ICBOOST(https://www.ti.com/tool/MMWAVEICBOOST )

    interested more in

    c.  tap in the SYNC_IN signal at RA8A or R157 to blue wire

    since we want to keep our sensor suite small.

    We used a microcontroller chip to provide 10Hz PWM wave as the trigger signal.

    The high voltage duration in each cycle of the PWM is 4us, per the discussions at [here](https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1231464/iwr6843aopevm-hardware-triggering-sync_in-pulse-requirements ).

    also I have seen some people report triggering success as "I did run the radar with a hardware trigger at pulse width 50 us and  the rise time 3.51 us!" (https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/972613/iwr6843isk-hardware-trigger )

    I found RA8A or R157 in the Design Files 6843 Rev G_PROC091G at (https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1122617/iwr6843aopevm-is-there-design-file-for-iwr6843aopevm-rev-g?tisearch=e2e-sitesearch&keymatch=iwr6843aop%252520rev%252520g ) The 3D PCB in pdf is beautiful.

    So RA8A is at J2 22pin, and R157 is at J11 16pin.

    1. If I connect my PWM wave pin to the J2 22pin and my ground pin to the J2 ground pin say 20,

    the wiring for triggering will be completed, right?

    2. BTW, what is blue wire? Pardon me for the seemingly naive question as I don't want to ruin the board by ignorant hacking.

    Thank you for the assistance.

  • Hi,

    The high voltage duration in each cycle of the PWM is 4us

    The high voltage duration should be of 1us for IWR6843AOP device. Please see the clarification at the end of thread.

    You can find the circuit schematic and assembly file in the below design file to locate RA8A and R157 in the IWR6843AOPEVM board.

    https://www.ti.com/lit/zip/swrr166

    So RA8A is at J2 22pin, and R157 is at J11 16pin.

    Yes, that is correct.

    1. If I connect my PWM wave pin to the J2 22pin and my ground pin to the J2 ground pin say 20,

    the wiring for triggering will be completed, right?

    Yes. the understanding is correct. However, HW triggering should be selected in the MMWAVE-STUDIO software Trigger Select option for the device to recognize that each frame would be triggered by rising edge of the SYNC_IN pulse and not software API. 

    2. BTW, what is blue wire? Pardon me for the seemingly naive question as I don't want to ruin the board by ignorant hacking.

    Blue wiring is a neutral wire that carries electricity away from an appliance. Like bringing out either male or female header pin/ jumper at the end of the circuit or at the location where the signal needs to be tapped in.

    Regards

    Ankit

  • Thank you very much, Ankit. I think you have resolved my issue. I will get my hands dirty to carry out the plan.

    Edit:

    Today I tried out the plan with a Microcontroller and a IWR6843AOPEVM, but it did not work.

    Here is my setup

    I plugged a samtec cable to the ICBoost socket(J2) on IWR6843AOPEVM, the pin 20 and pin 22 of J2 are ground, and sync_in, resp,

    I picked out the two wires for the two pins from the cable and connected them to the microcontroller pins that outputs 20 Hz PWM with 3.3 V duration at 1 us.

    The two wires from the samtec cable is the number 10 and 11 wires (corresponding to pin 20 and 22, resp.). I have double checked this.

    I welded the two wires to two extra wires for convenience. I think the welding should be good.

    The PWM output is confirmed by an oscilloscope.

    Then I ran the ROS1 driver with the below cfg, and no radar point clouds are published.

    ```

    % ***************************************************************
    % Created for SDK ver:03.05
    % Created using Visualizer ver:3.6.0.0
    % Frequency:60
    % Platform:xWR68xx_AOP
    % Scene Classifier:best_range
    % Azimuth Resolution(deg):30 + 30
    % Range Resolution(m):0.063
    % Maximum unambiguous Range(m):20
    % Maximum Radial Velocity(m/s):4.02
    % Radial velocity resolution(m/s):0.51
    % Frame Duration(msec):50
    % RF calibration data:None
    % ***************************************************************
    sensorStop
    flushCfg
    dfeDataOutputMode 1
    channelCfg 15 7 0
    adcCfg 2 1
    adcbufCfg -1 0 1 1 1
    profileCfg 0 60 63 7 39.75 0 0 75 1 399 12499 0 0 158
    chirpCfg 0 0 0 0 0 0 0 1
    chirpCfg 1 1 0 0 0 0 0 2
    chirpCfg 2 2 0 0 0 0 0 4
    frameCfg 0 2 16 0 45 2 0
    lowPower 0 0
    guiMonitor -1 1 1 0 0 0 1
    cfarCfg -1 0 2 8 4 3 0 15 1
    cfarCfg -1 1 0 4 2 3 1 15 1
    multiObjBeamForming -1 1 0.5
    clutterRemoval -1 0
    calibDcRangeSig -1 0 -5 8 256
    extendedMaxVelocity -1 0
    lvdsStreamCfg -1 0 0 0
    compRangeBiasAndRxChanPhase 0.0 1 0 -1 0 1 0 -1 0 1 0 -1 0 1 0 -1 0 1 0 -1 0 1 0 -1 0
    measureRangeBiasAndRxChanPhase 0 1.5 0.2
    CQRxSatMonitor 0 3 4 97 0
    CQSigImgMonitor 0 97 8
    analogMonitor 0 0
    aoaFovCfg -1 -90 90 -90 90
    cfarFovCfg -1 0 0 19.99
    cfarFovCfg -1 1 -4.05 4.05
    calibData 0 0 0
    sensorStart

    ```

    If I change the frameCfg line to "0 2 16 0 45 1 0", then the point clouds msgs will stream continuously. Note I only changes the trigger mode here.

    I have gone through the requirements about hardware triggering. There are some requirements on the time between frames, and the gap between the end of a frame and the trigger. I am not sure if the above cfg satisfy these requirements.

    Can you please pinpoint what I have missed?

  • Hi Josh,

    The SDK does not support this feature. Only software trigger is supported over SDK. If you wish to perform HW trigger you may want to use MMWAVE-STUDIO interface.

    Regards

    Ankit

  • I think I missed your earlier point "However, HW triggering should be selected in the MMWAVE-STUDIO software Trigger Select option for the device to recognize that each frame would be triggered by rising edge of the SYNC_IN pulse and not software API. " I will learn the MMWave Studio software.

    But it seems I need the DCA1000 board in order to tackle with IWR6843AOPEVM in mmWave studio according to [here](https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/959490/iwr6843aopevm-how-to-use-mmwavestudio-with-iwr6843aopevm).

    I can get access to this board in order to run mmWave Studio.

    a. But can I remove DCA1000 from AOPEVM after I have enabled the HW trigger with the mmWave Studio?

    Suppose I have enabled HW trigger in mmWave Studio,

    b. can I viz the radar point clouds with the Demo visualizer (with the frameCfg trigger mode 2)?

    c. can I use the ROS1 driver to get data with the HW trigger enabled?

    Thank you for your assistance.

  • Hi Josh,

    You can order DCA1000 board here.

    DCA1000EVM Evaluation board | TI.com

    a. But can I remove DCA1000 from AOPEVM after I have enabled the HW trigger with the mmWave Studio?

    No, you cannot disconnect the DCA1000 board from the AOPEVM. The DCA1000 should send to device a HW trigger notification every frame while you trigger 20 Hz PWM with 3.3 V duration at 1 us at SYNC_IN pin.

    I will pass the thread to software expert for b) and c)

    Regards

    Ankit