Bluetooth: Peripheral CTS client
The Peripheral CTS client sample demonstrates how to use the GATT Current Time Service (CTS) Client.
The sample supports the following development kits:
When built for an
_ns build target, the sample is configured to compile and run as a non-secure application with Cortex-M Security Extensions enabled.
Therefore, it automatically includes Trusted Firmware-M that prepares the required peripherals and secure services to be available for the application.
The sample also requires a device running a CTS Server to connect with (for example, a Bluetooth® Low Energy dongle and nRF Connect for Desktop).
The CTS client sample implements a Current Time Service client. It uses the Current Time Service to read the current time. The time received is printed on the UART.
- LED 1:
Blinks, toggling on/off every second, when the main loop is running and the device is advertising.
- LED 2:
Lit when connected.
- Button 1:
Read the current time.
This sample can be found under
samples/bluetooth/peripheral_cts_client in the nRF Connect SDK folder structure.
When built as firmware image for the
_ns build target, the sample has Cortex-M Security Extensions (CMSE) enabled and separates the firmware between Non-Secure Processing Environment (NSPE) and Secure Processing Environment (SPE).
Because of this, it automatically includes the Trusted Firmware-M (TF-M).
To read more about CMSE, see Processing environments.
To build the sample with Visual Studio Code, follow the steps listed on the How to build an application page in the nRF Connect for VS Code extension documentation. See Configuring and building an application for other building scenarios, Programming an application for programming steps, and Testing for general information about testing and debugging in the nRF Connect SDK.
After programming the sample to your development kit, you can test it with nRF Connect for Desktop by performing the following steps.
Connect to the kit that runs this sample with a terminal emulator (for example, nRF Connect Serial Terminal). See Testing and optimization for the required settings and steps.
Reset the kit.
Start nRF Connect for Desktop
Open the Bluetooth Low Energy app and select the connected dongle that is used for communication.
Open the SERVER SETUP tab. Click the dongle configuration and select Load setup. Load the
cts_central.ncsfile that is located under
samples/bluetooth/peripheral_cts_clientin the nRF Connect SDK folder structure.
Click Apply to device.
Open the CONNECTION MAP tab. Click the dongle configuration and select Security parameters. Check Perform Bonding, and click Apply.
Set the value of Current Time Service > Current Time to
C2 07 0B 0F 0C 22 38 06 80 02and click Write.
Connect to the device from the app. The device is advertising as “Nordic_CTS”.
Wait until the bond is established. Verify that the UART data is received as follows:
Connected xx:xx:xx:xx:xx:xx (random) The discovery procedure succeeded Security changed: xx:xx:xx:xx:xx:xx (random) level 2 Pairing completed: xx:xx:xx:xx:xx:xx (random), bonded: 1
Press Button 1 on the kit. Verify that the current time printed on the UART matches the time that was input in the Current Time characteristic (UUID 0x2A2B):
Current Time: Date: Day of week Saturday Day of month 15 Month of year November Year 1986 Time: Hours 12 Minutes 34 Seconds 56 Fractions 128/256 of a second Adjust Reason: Daylight savings 0 Time zone 0 External update 1 Manual update 0
Change the value of Current Time Service > Current Time to
C2 07 0B 0F 0D 25 2A 06 FE 08. It generates a notification. Verify that the current time printed on the UART matches the time that was input:
Current Time: Date: Day of week Saturday Day of month 15 Month of year November Year 1986 Time: Hours 13 Minutes 37 Seconds 42 Fractions 254/256 of a second Adjust Reason: Daylight savings 1 Time zone 0 External update 0 Manual update 0
Disconnect the device in the Bluetooth Low Energy app.
As bond information is preserved by the Bluetooth Low Energy app, you can immediately reconnect to the device by clicking the Connect button again.
This sample uses the following nRF Connect SDK libraries:
In addition, it uses the following Zephyr libraries:
The sample also uses the following secure firmware component: