MXChip AZ3166 Telemetry Frequency

Question

MXChip AZ3166 Telemetry Frequency

Jonathan GOH 46

Hi I recently got my hands on a MXChip AZ3166 and established a connection to IoT Central. May I know if I am able to configure the rate at which the telemetry messages are sent? For example, instead of sending the data for Temperature, Humidity and Pressure every 40 seconds, can it be every 1 minute instead? Thank you.

Accepted answer

0 additional answers

Your answer

Answer 1

chbeier 1,871

Hi @Jonathan GOH ,

If you followed the quickstart-devkit-mxchip-az3166 to connect the MXChip DevKit to IoT Central, the resulting device has a desired Property named telemetryInterval. Within IoT Central you can see the current configuration in the device details on the About page, it should be set to 10 seconds.

Usually, there should be also a Property tab next to Commands what you can use to set writeable properties. As it does not exist, you can create a Job to configure the Telemetry Interval property. The docs contain a general description howto-manage-devices-in-bulk. An example job configuration to set the Telemetry Interval property is shown in the picture below, simply select the right device group, job type and property name from the drop downs.

You can also configure the delivery options or enable a schedule for the job in the additional steps. If you hit run you should see the job execution status on the next page. To see a history of your defined jobs just select the Jobs item in the left-hand menu.

On the device details page you should see the updated Telemetry Interval property and your raw data timestamps should reflect the new send interval.

Jonathan GOH 46 Reputation points

2022-03-04T02:16:54.503+00:00

Hi @chbeier ,

Thank you so much for the help and references, I have successfully changed the Telemetry Interval. Regarding the raw data output, is it possible for all the parameters to be sent in one telemetry message, instead of the default one?
chbeier 1,871 Reputation points

2022-03-04T12:30:28.04+00:00

The send behavior is defined in the device code (.\MXChip\AZ3166\app\nx_client.c line 336) within the telemetry_cb function. Whenever a callback occurs the azure_iot_nx_client_publish_telemetry function is executed for the current telemetry state, and a message is sent to IoT Hub.

To change the send behavior, this might be a starting point. Be aware, the MXChip has limited resources. Thus, creating a message with all telemetry values might require additional changes in the code.

chbeier 1,871

Update:

I created some example code to send a message with all telemetry values.

Within nx_client.c I shortened the Device telemetry names, otherwise it did not run

    // Device telemetry names
...
    #define TELEMETRY_MAGNETOMETERX     "magnetX"
    #define TELEMETRY_MAGNETOMETERY     "magnetY"
    #define TELEMETRY_MAGNETOMETERZ     "magnetZ"
    #define TELEMETRY_ACCELEROMETERX    "accelX"
    #define TELEMETRY_ACCELEROMETERY    "accelY"
    #define TELEMETRY_ACCELEROMETERZ    "accelZ"
    #define TELEMETRY_GYROSCOPEX        "gyroX"
    #define TELEMETRY_GYROSCOPEY        "gyroY"
    #define TELEMETRY_GYROSCOPEZ        "gyroZ"
    ...

and added a new append_device_telemetry_all() function

static UINT append_device_telemetry_all(NX_AZURE_IOT_JSON_WRITER* json_writer)
{
    if (append_device_telemetry(json_writer) ||
        append_device_telemetry_accelerometer(json_writer) ||
        append_device_telemetry_gyroscope(json_writer) ||
        append_device_telemetry_magnetometer(json_writer))
    {
        return NX_NOT_SUCCESSFUL;
    }

    return NX_AZURE_IOT_SUCCESS;
}

and finally, I changed the telemtry_cb() function to append all telemetry data

static void telemetry_cb(AZURE_IOT_NX_CONTEXT* nx_context)
{
    azure_iot_nx_client_publish_telemetry(&azure_iot_nx_client, NULL, append_device_telemetry_all);
}

Jonathan GOH 46 Reputation points

2022-03-07T07:10:14.097+00:00

Hi @chbeier ,

Thank you for your update, this was exactly what I was going for! Really appreciate your help with this! Thank you so much

Share via

MXChip AZ3166 Telemetry Frequency

0 additional answers

Your answer