ANT and BLE Heart Rate Monitor Relay Application

Overview

The ANT and BLE Heart Rate Monitor Relay Application shows the concurrent use of ANT and BLE protocols. This application exposes the HR (Heart Rate) GATT Service. In addition, it implements the ANT Heart Rate Profile Receiver. The aggregated data received from ANT is relayed and sent as BLE notifications.

This application is based on the zephyr/samples/bluetooth/peripheral_hr and ant/samples/ant_plus/ant_hrm/hrm_rx samples.

Channel configuration

This example uses the default channel configuration:

Parameter	Transmitter	Receiver
Channel type	Master (0x10)	Slave (0x00)
Network key	ANT+	ANT+
RF channel	57 (2457 MHz)	57 (2457 MHz)
Device number	0x31 (49)	0x31 (49)
Device type	0x78 (120)	0x78 (120)
Transmission type	0x01	0x01
Channel period	8070 (4.06 Hz)	8070 (4.06 Hz)

Requirements

Hardware platforms	PCA	Board name	Build target
nRF5340 DK	PCA10095	nrf5340dk_nrf5340	nrf5340dk_nrf5340_cpuapp

Building and running

This sample can be found under ant/samples/ant_plus/ant_hrm/hrm_rx in the nRF Connect SDK folder structure.

ANT+ Network Key

This sample selects ‘’CONFIG_ANT_KEY_MANAGER’’ to provide access to ant_plus_key_set(). This library function configures the pre-defined ANT+ Network Key for ANT+ devices. Note that network keys, transmission type, device type IDs and RF channels are assigned and regulated to maintain network integrity, and interoperability, except for the default public network.

For more information on Network Keys, visit https://www.thisisant.com/developer/ant-plus/ant-plus-basics/network-keys.

Testing the HRM Relay

Test the Heart Rate Relay Application with the nRF Connect app, which is available on both iOS (App Store) and Android (Google Play).

You can also test the application with nRF Connect for Desktop by performing the following steps:

Compile and program the application. Observe that the BSP_INDICATE_ADVERTISING state is indicated.
Connect to the device from nRF Connect (the device is advertising as ‘Nordic_HRM’).
Observe that the services are shown in the connected device and that you can start receiving values for the Heart Rate Service by clicking the Play button.
Compile and program the ANT Heart Rate Monitor (HRM) transmitter example on the second board as a peer ANT device. This sample can be found under ant/samples/ant_plus/ant_hrm/hrm_tx in the nRF Connect SDK folder structure. Alternatively, you can configure a simulated Heart Rate Sensor in SimulANT+.
On the nRF DK side, connect to the cpuapp virtual COM port to view the ANT+ HRM pages received by the Relay Application.
Observe that the BLE Heart Rate notifications values received in the nRF Connect app the correspond to modifications made on the transmitter device. This could be simulated data or button presses if using ANT+ HRM Transmitter sample, or manual modifications to the data fields if using SimulANT+.