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 Modem library and LTE link controller library.
The sample supports the following development kits:
Additionally, it supports X86 Emulation (QEMU).
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
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.
See Configuring your application for information about how to permanently or temporarily change the configuration.
You can configure the following options:
- UDP data upload size configuration¶
This configuration option sets the number of bytes to be transmitted to the server.
- UDP data upload frequency configuration¶
This configuration option sets the frequency with which the sample transmits data to the server.
- UDP Server IP Address configuration¶
This configuration option sets the static IP address of the server.
- UDP server port configuration¶
This configuration option sets the server address port number.
- PSM mode configuration¶
This configuration option, if set, allows the sample to request PSM from the modem or cellular network.
- eDRX mode configuration¶
This configuration option, if set, allows the sample to request eDRX from the modem or cellular network.
- RAI configuration¶
This configuration option, if set, allows the sample to request RAI for transmitted messages.
PSM, eDRX and RAI value or timers are set via the configurable options for the LTE link controller library.
Below configurations are recommended for low power behavior:
CONFIG_LTE_PSM_REQ_RATset to 0.
CONFIG_UDP_EDRX_ENABLEset to false.
CONFIG_UDP_RAI_ENABLEset to true for NB-IoT. It is not supported for LTE-M.
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.
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.
This sample can be found under
samples/nrf9160/udp in the nRF Connect SDK folder structure.
See Building and programming an 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.
You can also configure it to use TF-M instead of Secure Partition Manager.
After programming the sample to your device, test it by performing the following steps:
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.
Connect to the kit with a terminal emulator (for example, PuTTY). See How to connect with PuTTY for the required settings.
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.
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
spm.conf configuration files.
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 126.96.36.199, 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 188.8.131.52, port number 2469 RRC mode: Connected RRC mode: Idle Transmitting UDP/IP payload of 38 bytes to the IP address 184.108.40.206, port number 2469 RRC mode: Connected RRC mode: Idle