ANT: ANT+ Bicycle Speed and Cadence Transmitter

The Bicycle Speed and Cadence Transmitter sample shows the usage of the ANT+ Bicycle Speed and Cadence profile.

Overview

This sample simulates a Bicycle Speed and Cadence Combined transmitter. It transmits the speed and cadence information in the main data page (page 5). Device-specific information is transmitted at a slower rate in the background data pages (pages 1-4). The application prints out outgoing page data. The actual channel state is indicated by the ANT channel state indicator.

On dual core, this sample uses the ‘’CONFIG_ANT_NP’’ and ‘’CONFIG_ANT_INCLUDE_NP_CHILD_IMAGE’’ Kconfig options to automatically configure a child image on the network core.

Channel configuration

This example uses the default channel configuration for the combined BSC sensor:

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*	0x79 (121)	0x79 (121)
Transmission type	0x01	0x01
Channel period*	8086 (4.05 Hz)	8086 (4.05 Hz)

*Parameters depend on type of BSC sensor configured

Requirements

Hardware platforms	PCA	Board name	Build target
nRF5340 DK	PCA10095	nrf5340dk_nrf5340	nrf5340dk_nrf5340_cpuapp
nRF52840 DK	PCA10056	nrf52840dk_nrf52840	nrf52840dk_nrf52840

Building and running

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

You can select how the profile information is modified with the ‘’CONFIG_BSC_TX_MODIFICATION_TYPE’’ value. There are two ways to modify the profile information (speed and cadence):

• Automatic (‘’UPDATE_AUTO’’), which means that the speed and cadence values rise and fall periodically.

• Button controlled (‘’UPDATE_MANUAL’’), which means that the data can be modified by pressing the buttons. Pressing Button 1 stops increases in the speed/cadence values. Pressing Button 2 starts increasing the speed/cadence values.

You can also select the sensor type with the ‘’CONFIG_SENSOR_TYPE’’ value. There are three types of sensors that change which data is being transmitted (speed, cadence, or both):

• Combined Sensor (121), which will transmit both speed and cadence data.

• Cadence Sensor (122), which will only transmit cadence data.

• Speed Sensor (123), which will only transmit speed data.

ANT+ Network Key

This sample selects CONFIG_ANT_KEY_MANAGER to provide access to ant_plus_key_set() (See ANT Key Manager Library). 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 Transmitter using ANTware II:

1. Compile and program the Bicycle Speed and Cadence Transmitter.

2. Run ANTware II. Select your ANT PC dongle (for example, ANTUSB-m) from the available devices.

3. Configure the device channel by loading the channel profile configuration from the following file:

   For a Combined Sensor:

   ant\samples\ant_plus\ant_bsc\bsc_tx\bsc_combined_rx_device_profile.xml

   For a Cadence Sensor:

   ant\samples\ant_plus\ant_bsc\bsc_tx\bsc_cadence_rx_device_profile.xml

   For a Speed Sensor:

   ant\samples\ant_plus\ant_bsc\bsc_tx\bsc_speed_rx_device_profile.xml

   Alternatively, you can configure the device channel manually:

   For a Combined Sensor:

   • Set the channel assignment to Slave.

   • Set the channel ID to “0, 121, 0”.

   • On the Basic tab, set the channel period to 8086 cycles (4.052 Hz) and the radio frequency to 2457 MHz.

   • Keep the default for all other settings.

   For a Cadence Sensor:

   • Set the channel assignment to Slave.

   • Set the channel ID to “0, 122, 0”.

   • On the Basic tab, set the channel period to 8102 cycles (4.044 Hz) and the radio frequency to 2457 MHz.

   • Keep the default for all other settings.

   For a Speed Sensor:

   • Set the channel assignment to Slave.

   • Set the channel ID to “0, 123, 0”.

   • On the Basic tab, set the channel period to 8118 cycles (4.036 Hz) and the radio frequency to 2457 MHz.

   • Keep the default for all other settings.

   Use the Info/Net tab to enter the ANT+ Network Key and select Set Network Key on Net #0.

4. Click the Auto-Open button. Observe that messages describing the received payload appear for each ANT message. These messages should look similar to the following fragment:

   Received BROADCAST_DATA_0x4E
       :: 4e, 00-05-01-FF-FF-43-5C-6A-09
   Received BROADCAST_DATA_0x4E
       :: 4e, 00-05-01-FF-FF-43-5C-6A-09
   Received BROADCAST_DATA_0x4E
       :: 4e, 00-05-01-FF-FF-43-5C-6A-09
   Received BROADCAST_DATA_0x4E
       :: 4e, 00-84-FF-C8-22-43-5C-6A-09
   Received BROADCAST_DATA_0x4E
       :: 4e, 00-84-FF-C8-22-43-5C-6A-09
   Received BROADCAST_DATA_0x4E
       :: 4e, 00-84-FF-C8-22-43-5C-6A-09
   Received BROADCAST_DATA_0x4E
       :: 4e, 00-84-FF-C8-22-43-5C-6A-09
   Received BROADCAST_DATA_0x4E
       :: 4e, 00-05-01-FF-FF-43-5C-6A-09
   

   Each message can be decoded according to the ANT message protocol and the Bicycle Speed and Cadence ANT+ device profile.

Testing the BSC examples with the ANT+ Simulator tools

To use the ANT+ Simulator tools, the ANT+ Network Key must be configured (ie. using ant_plus_key_set() as shown in the sample).

You can then use the ANT+ Display Simulator to test the BSC Transmitter. See the documentation of the ANT+ Simulator tools at thisisant.com for information about how to use these tools.