ANT: Multi Channel Encrypted RX

The Multi Channel Encrypted examples demonstrate transmitter and receiver operations of encrypted ANT channel(s).

Overview

On dual core, this sample uses sysbuild to add a network core image to the build by defining the ‘’NRF_DEFAULT_ANT_ONLY’’ with a default value of ‘’y’’ in Kconfig.sysbuild.

The ‘’CONFIG_ANT_ENCRYPTED_CHANNELS’’ Kconfig must be set to a value between 1 and ‘’CONFIG_ANT_TOTAL_CHANNELS_ALLOCATED’’ Kconfig to allocate encrypted channnels within the ANT stack library. It must be set on the radio-adjacent or CONFIG_ANT_LIBRARY_CORE. In the dual core case, this is set in the network core image configuration in the sysbuild/ant_rpc subdirectory.

This sample utilizes the ANT Encrypt Config Library to configure the encrypted channel(s). The following configurations apply:

• ‘’CONFIG_ANT_ENCRYPTION_NUM_CHANNELS’ Kconfig specifies the number of desired encrypted channels to be managed and should be set to a value between 1 and ‘’CONFIG_ANT_ENCRYPTED_CHANNELS’’. In this example, the default configuration of 1 is used.

• ‘’ANT_ENCRYPTION_NEGOTIATION_SLAVE’’ Kconfig is applicable only for a receiver and is used to manage encryption negotiations with an encrypted transmitter. In this example, this is set to ‘’y’’ in the cpuapp image configuration.

Channel configuration

This example uses the following channel configuration:

Parameter	Transmitter	Receiver
Channel type	Master (0x10)	Slave (0x00)
Network key	Public	Public
RF channel	66 (2466 MHz)	66 (2466 MHz)
Device number	ANT Ch # + 1	ANT Ch # + 1
Device type	0x02	0x02
Transmission type	0x01	0x01
Channel period	8192 (4 Hz)	8192 (4 Hz)

Requirements

Hardware platforms	PCA	Board name	Build target
nRF5340 DK	PCA10095	nrf5340dk/nrf5340	nrf5340dk/nrf5340/cpuapp
nRF52840 DK	PCA10056	nrf52840dk/nrf52840	nrf52840dk/nrf52840

Configuration

This sample configuration is split into the following two files:

• generic configuration is available in the prj.conf file (single core, or dual core cpuapp)

• configuration for the ant_rpc network core image is stored in the sysbuild/ant_rpc subdirectory (dual core cpunet)

Building and running

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

Testing

After programming the sample to your development kit and paired with the ANT multi channels encrypted tx sample application programmed on another development kit, the virtual COM port will show corresponding encrypted EVENT_RX messages becoming decrypted after successful negotiation with the transmitter.

[00:00:00.436,218] <inf> ant_multi_channels_encrypted_rx: num_decrypted_channels: 0
[00:00:00.440,582] <inf> main: ANT Encrypted Broadcast RX example started
[00:00:02.112,670] <inf> main: CH 0 - EVENT_RX - 09 4E 00 0C B3 53 0F 01 E3 19 41
[00:00:02.362,243] <inf> main: CH 0 - EVENT_RX - 09 4E 00 96 97 63 5B 86 55 43 77
[00:00:02.381,561] <inf> ant_multi_channels_encrypted_rx: num_decrypted_channels: 1
[00:00:02.381,591] <inf> main: CH 0 - EVENT_ENCRYPT_NEGOTIATION_SUCCESS - 07 40 00 01 38 01 23 45 67
[00:00:02.612,304] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 19
[00:00:02.862,304] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 1A
[00:00:03.112,274] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 1B
[00:00:03.362,335] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 1C
[00:00:03.612,335] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 1D
[00:00:03.862,335] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 1E
[00:00:04.112,274] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 1F
[00:00:04.362,274] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 20
[00:00:04.612,274] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 21
[00:00:04.862,274] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 22
[00:00:05.112,243] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 23
[00:00:05.362,304] <inf> main: CH 0 - EVENT_RX - 09 4E 00 00 00 00 00 00 00 00 24