ANT: ANT+ Heart Rate Monitor Receiver

The Heart Rate Monitor Receiver sample shows the usage of the ANT+ Heart Rate Monitor profile.

Overview

This sample simulates a Heart Rate Monitor Receiver. The Receiver application connects to the nearest heart rate monitor (HRM) in range and prints out incoming page data. The actual channel state is indicated by the ANT channel state indicator.

This sample uses the ‘’CONFIG_ANT_NP’’ and ‘’CONFIG_ANT_INCLUDE_NP_CHILD_IMAGE’’ Kconfig options to automatically configure a child image for multicore platforms.

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 with ANTware II

After programming the sample to your development kit, you can test the Heart Rate Monitor Receiver using ANTware II:

  1. Compile and program the Heart Rate Monitor Receiver.

  2. Compile and program the HRM Transmitter. Alternatively, use SimulANT+ as described below.

    On the nRF DK side, the virtual COM port will show the ANT+ HRM pages received.

    [00:00:00.273,498] <inf> hrm_rx: ANT+ HRM RX sample starting...
    [00:00:00.275,329] <inf> ant_hrm: ANT HRM channel 0 init
    [00:00:00.276,611] <inf> ant_hrm: ANT HRM channel 0 open
    [00:00:00.366,912] <inf> ant_hrm: HRM RX Page Number: 0
    [00:00:00.366,912] <inf> ant_hrm_page_0: Heart beat count:                 97
    [00:00:00.366,912] <inf> ant_hrm_page_0: Computed heart rate:              72
    [00:00:00.366,943] <inf> ant_hrm_page_0: Heart beat event time:            16.804s
    
    [00:00:00.366,943] <inf> hrm_rx: Page was updated
    [00:00:00.613,159] <inf> ant_hrm: HRM RX Page Number: 0
    [00:00:00.613,159] <inf> ant_hrm_page_0: Heart beat count:                 97
    [00:00:00.613,189] <inf> ant_hrm_page_0: Computed heart rate:              72
    [00:00:00.613,220] <inf> ant_hrm_page_0: Heart beat event time:            16.804s
    

Testing the HRM examples with the ANT+ Simulator tools

You can use the SimulANT+ Heart Rate Sensor Simulator to test the HRM Receiver. Make sure the Device Number matches the Channel Configuration above (0x31). See the documentation of the ANT+ Simulator tools at thisisant.com for information about how to use these tools.