nRF9160: UDP

The UDP sample demonstrates the sequential transmission of UDP packets to a predetermined server identified by an IP address and a port. The sample uses the BSD library and LTE link controller library.

Requirements

The sample supports the following development kits:

Hardware platforms

PCA

Board name

Build target

Thingy:91

PCA20035

thingy91_nrf9160

thingy91_nrf9160ns

nRF9160 DK

PCA10090

nrf9160dk_nrf9160

nrf9160dk_nrf9160ns

Additionally, it supports X86 Emulation (QEMU).

Overview

The sample acts directly on socket level abstraction. It configures a UDP socket and continuously transmits data over the socket to the modem’s TCP/IP stack, where the data eventually gets transmitted to a server specified by an IP address and a port number. To control the LTE link, it uses the LTE link controller library and requests Power Saving Mode (PSM), extended Discontinuous Reception (eDRX) mode and Release Assistance Indication (RAI) parameters. These parameters can be set through the sample configuration file prj.conf.

You can configure the frequency with which the packets are transmitted and the size of the UDP payload through the Kconfig system. In addition to setting of the above options, you can also set the various LTE parameters that are related to current consumption for adding low power behavior to the device.

The UDP sample can be used to characterize the current consumption of the nRF9160 SiP. This is due to the simple UDP/IP behavior demonstrated by the sample, which makes it suitable for current measurement.

Measuring Current

For measuring current on an nRF9160 DK, it must first be prepared as described in Measuring Current on nRF9160 DK. If you are measuring current on a Thingy:91, see Measuring Current on Thingy:91.

Configuration

See Configuring your application for information about how to permanently or temporarily change the configuration.

You can configure the following options:

Configuration options

CONFIG_UDP_DATA_UPLOAD_SIZE_BYTES - UDP data upload size configuration

This configuration option sets the number of bytes to be transmitted to the server.

CONFIG_UDP_DATA_UPLOAD_FREQUENCY_SECONDS - UDP data upload frequency configuration

This configuration option sets the frequency with which the sample transmits data to the server.

CONFIG_UDP_SERVER_ADDRESS_STATIC - UDP Server IP Address configuration

This configuration option sets the static IP address of the server.

CONFIG_UDP_SERVER_PORT - UDP server port configuration

This configuration option sets the server address port number.

CONFIG_UDP_PSM_ENABLE - PSM mode configuration

This configuration option, if set, allows the sample to request PSM from the modem or cellular network.

CONFIG_UDP_EDRX_ENABLE - eDRX mode configuration

This configuration option, if set, allows the sample to request eDRX from the modem or cellular network.

CONFIG_UDP_RAI_ENABLE - RAI configuration

This configuration option, if set, allows the sample to request RAI for transmitted messages.

Note

PSM, eDRX and RAI value or timers are set via the configurable options for the LTE link controller library.

Additional configuration

Below configurations are recommended for low power behavior:

PSM and eDRX timers are set with binary strings that signify a time duration in seconds. See Power saving mode setting section in AT commands reference document for a conversion chart of these timer values.

Note

The availability of power saving features or timers is entirely dependent on the cellular network. The above recommendations may not be the most current efficient if the network does not support the respective feature.

Configuration files

The sample provides predefined configuration files for the following development kits:

  • prj.conf : For nRF9160 DK and Thingy:91

  • prj_qemu_x86: For x86 Emulation (QEMU)

They are located in samples/nrf9160/udp folder.

Building and running

This sample can be found under samples/nrf9160/udp in the nRF Connect SDK folder structure.

See Building and programming a sample application for information about how to build and program the application.

The sample is configured to compile and run as a non-secure application on nRF91’s Cortex-M33. Therefore, it automatically includes the Secure Partition Manager that prepares the required peripherals to be available for the application.

Testing

After programming the sample to your device, test it by performing the following steps:

  1. Connect the kit to the computer using a USB cable. The kit is assigned a COM port (Windows) or ttyACM device (Linux), which is visible in the Device Manager.

  2. Connect to the kit with a terminal emulator (for example, PuTTY). See How to connect with PuTTY for the required settings.

  3. Observe that the sample shows the UART output from the device. Note that this is an example and the output need not be identical to your observed output.

Note

Logging output is disabled by default in this sample in order to produce the lowest possible amount of current consumption. To enable logging, set the CONFIG_SERIAL option in the prj.conf and spm.conf configuration files.

Sample output

The following serial UART output is displayed in the terminal emulator:

*** Booting Zephyr OS build v2.3.0-rc1-ncs1-1451-gb160c8c5caa5  ***
UDP sample has started
LTE cell changed: Cell ID: 33703711, Tracking area: 2305
PSM parameter update: TAU: 110287, Active time: 61024
RRC mode: Connected
Network registration status: Connected - roaming

PSM parameter update: TAU: -1, Active time: -1
Transmitting UDP/IP payload of 38 bytes to the IP address 8.8.8.8, port number 2469
PSM parameter update: TAU: 3600, Active time: 0
RRC mode: Idle

Transmitting UDP/IP payload of 38 bytes to the IP address 8.8.8.8, port number 2469
RRC mode: Connected
RRC mode: Idle

Transmitting UDP/IP payload of 38 bytes to the IP address 8.8.8.8, port number 2469
RRC mode: Connected
RRC mode: Idle

Dependencies

This sample uses the following nRF Connect SDK libraries:

  • lib/bsd_lib

  • lib/lte_link_control

In addition, it uses the following sample: