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CC3220MODA: Does NWP need to be active to enter LPDS?

Part Number: CC3220MODA
Hi Support,

For the CC3220, does the network processor need to be active for the main processor to enter LPDS mode? Or can all networking activity be disabled during LPDS?

I don't need or want the NWP to be enabled during LPDS. However, when I try putting my hardware to sleep (before calling `sl_Start()`) I notice that the system current only reduces to about 3.5mA. Then, I looked at the `power_measurement.c` demo and noticed that `sl_Start()` is called before enabling the power policy. So, I am now calling `sl_Start()` before enabling LPDS and the device appears to go into LPDS correctly. But is there a way to disable the Wi-Fi beacons? The power draw between the beacons is what I am expecting - about 135uA - but I don't require any network connection at this stage of the application.

Thanks in advance,
Brian
// power_measure.c
    case UseCase_LPDS :
        status = sl_Start(0,0,0);
        if (status < 0)
        {
            UART_PRINT("unable to start the device \n\r");
            LOOP_FOREVER();
        }
        /* Enable LPDS policy */
        Power_enablePolicy();
        sem_wait(&PowerMeasure_CB.sem);
        break;
  • Hi Brian,

    The application MCU has a separate power policy from the NWP, so the NWP can be off. How are you testing MCU-only? There may be something else occuring in the application. Also, are you testing on a LaunchPad or a custom board?

    Best regards,

    Sarah

  • I'm testing by having a UDP packet sent at the end of LPDS. Eventually, I will need the NWP on, but it can be off for several seconds up until packet transmission. How can I make sure the NWP is completely off? Is there a power policy to disable the NWP altogether?

    I'm developing on a custom piece of hardware.

    Thanks,

    Brian

  • Hi Brian,

    After a power reset, the NWP is off. It turns on with sl_Start and off with sl_Stop.

    If the NWP is off, you can't be calling any sl_ APIs. So what is happening in the test application before sl_Start?

    Best regards,

    Sarah

  • Hi Sarah,

    Calling sl_Stop(0) before the LPDS policy is enabled resolved the main issue. The hardware is no longer performing any networking operations during LPDS. Thank you.

    But this is before sl_Start() was called by the application. Shouldn't the NWP be disabled before sl_Start() is called? Is there an initial configuration setting that causes the NWP to be turned on after boot?

    I'm using SDK 2.40.02.

    Thanks much,

    Brian

  • Hi Brian,

    What example are you starting with? There may be some sl_Start command hidden in the application. For example, in the power_measurement example, sl_WifiConfig() in the main starts the network processor to configure the NWP to set defaults.

    Best regards,

    Sarah

  • Hi Sarah,

    I'm not seeing a hidden sl_Start() call but I will assume that I am missing it somewhere. Thank you very much for your assistance.

    Brian