Bluetooth: Peripheral CTS client

The Peripheral CTS client sample demonstrates how to use the GATT Current Time Service (CTS) Client.

Overview

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.

Requirements

The sample supports the following development kits:

Hardware platforms

PCA

Board name

Build target

nRF5340 DK

PCA10095

nrf5340dk_nrf5340

nrf5340dk_nrf5340_cpuapp

nrf5340dk_nrf5340_cpuapp_ns

nRF52840 DK

PCA10056

nrf52840dk_nrf52840

nrf52840dk_nrf52840

nRF52833 DK

PCA10100

nrf52833dk_nrf52833

nrf52833dk_nrf52833

nRF52 DK

PCA10040

nrf52dk_nrf52832

nrf52dk_nrf52832

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).

User interface

LED 1:

  • Blinks with a period of 2 seconds, duty cycle 50%, when the main loop is running.

LED 2:

  • On when connected.

Button 1:

  • Read the current time.

Building and running

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

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

Testing

After programming the sample to your development kit, you can test it with nRF Connect for Desktop by performing the following steps.

  1. Connect to the kit that runs this sample with a terminal emulator (for example, PuTTY). See How to connect with PuTTY for the required settings.

  2. Reset the kit.

  3. Start nRF Connect for Desktop and select the connected dongle that is used for communication.

  4. Go to the Server setup tab. Click the dongle configuration and select Load setup. Load the cts_central.ncs file that is located under samples/bluetooth/peripheral_cts_client in the nRF Connect SDK folder structure.

  5. Click Apply to device.

  6. Go to the Connection Map tab. Click the dongle configuration and select Security parameters. Check Perform Bonding, and click Apply.

  7. Set the value of Current Time Service > Current Time to C2 07 0B 0F 0C 22 38 06 80 02 and click Write.

  8. Connect to the device from nRF Connect. The device is advertising as “Nordic_CTS”.

  9. 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

  10. 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

  11. 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

  12. Disconnect the device in nRF Connect.

  13. As bond information is preserved by nRF Connect, you can immediately reconnect to the device by clicking the Connect button again.

Dependencies

This sample uses the following nRF Connect SDK libraries:

In addition, it uses the following Zephyr libraries:

  • include/zephyr/types.h

  • lib/libc/minimal/include/errno.h

  • include/sys/printk.h

  • Bluetooth:

    • include/bluetooth/bluetooth.h

    • include/bluetooth/conn.h

    • include/bluetooth/uuid.h

    • include/bluetooth/gatt.h