Vela IF820 Series - Bluetooth 5.4 Dual-Mode Modules

If using MODUS Toolbox on the IF820 it can support Hands Free Profile (HFP) over the I2S/PCM interface. Infineon, in MODUS Toolbox, supports mSBC and CVSD audio CODECs in FW which is used in HFP.

SBC CODEC which is used as the compression algorithm for Advance Audio Distribution Profile (A2DP) could be done in FW as well but the I2S interface doesn’t support 44KHz/48KHz sample rates, thus, it can’t be used for A2DP.

There is no support for LE Audio.

By default, the Vela IF820 module is loaded with EZ-Serial firmware, which has Classic Bluetooth SPP data mode active by default.

The EZ-Serial firmware platform for Laird Vela IF820 series module supports Bluetooth Classic SPP service as a simple method to send and receive serial data over a Bluetooth connection. This operational mode is separated from the normal command mode where the API protocol may be used. When SPP data mode is active, any data received from an external host will be transmitted to the remote peer, and any data received from the remote peer will be sent out through the hardware serial interface to the external host.

To connect Vela IF820 via Bluetooth SPP profile using a computer (Windows) follow these steps:

1.    Click the Bluetooth icon on your Windows Taskbar or access the Bluetooth menu from Control Panel > All Control Panel Items > Devices and Printers. Select Add a device.

2.      Select device named “EZ-Serial XX:XX:XX_BT” and connect. Windows will install drivers for this device. You will find two ports associated with this device in Device Manager.

3.      Open a terminal application and connect to the COM port (typically the lower numbered COM port is the port to select).

Now you can transfer data between the terminal application in Windows and the terminal of the Laird Vela IF820 module.

There are two ways to disconnect from an SPP connection.

1. Using the CYSPP pin
2. Using the disconnect command in non-transparent mode

SPP can be controlled through the hardware GPIO on the EZ-Serial firmware platform for Laird Vela IF820 series module. Cyspp pin, which is also used for CYSPP, can be used to control the SPP connection state:

• By default, CYSPP pin is set in HIGH state.

• Once SPP connection is active, CYSPP pin will be set to LOW state.

• If CYSPP pin is set to HIGH by an ex ternal MCU while a SPP connection is active, the SPP connection will be terminated.

Note there is a jumper on the IF820 DVK that may be pulling CYSPP high which needs to be removed before using this method of disconnection.

In non-transparent mode, though SPP is connected, user still can use command mode. Data receive from SPP connection will arrive with event “.SPPD”. See the command protocol_set_parse_mode (SPPM, ID=1/1) to use non-transparent mode. See bt_disconnect (/BTDIS, ID=14/6)

Each variant of the Vela IF820, (integrated antenna, or external antenna connector) use a different power table. The script is not able to auto-detect which variant of the Vela IF820 is being flashed, therefore, users must ensure they have modified the script to select the correct firmware version for the variant of the IF820 they are programming. Of note, the Vela IF820 dongle uses the integrated antenna firmware.

For example, to select the external antenna firmware version of the v14.12.12 firmware to flash to the module, open the {} settings.jason file in VSCode. Locate the "ezserial_firmware" line and modify the path provided for the firmware to select the correct path in the VSCode workspace files for the v1.4.12.12-candidate_ext-ant/202309011_ezserial_app_VELA-IF820-EXT-ANT-EVK_141212_v1.4.12.12_download.hex. An example of the modified script is shown below:

{   

 "default_baud": "115200",    

"mini_driver": "${workspaceFolder}/files/minidriver-20820A1-uart-patchram.hex",    

"ezserial_firmware": "${workspaceFolder}/files/v1.4.12.12-candidate_ext-ant/202309011_ezserial_app_VELA-IF820-EXT-ANT-EVK_141212_v1.4.12.12_download.hex",    

"comport_BT900_device1": "/dev/cu.usbserial-AL04XL61"

Please see the Vela IF820 User Guide for additional information about modifying the {} settings.json file.

Does the Vela IF820 support more than one concurrent SPP connection when using EZ-Serial?

No, only a single SPP connection is supported with EZ-Serial. If multiple SPP connections are required, consider using Modus Toolbox.

Transparent data mode can be disabled with bit 1 of the SPPM command as below. This can be used in both text and binary parse modes

(<<) SPPM,M=2

(>>) @R,000A,SPPM,0000

Now when entering a SPP connection instead of going straight into transparent data mode EZ-Serial will remain in command mode and allow the use of commands such as 

Query Connections

(<<) /btqc

(>>) @R,0010,/BTQC,0000,C=01

(>>) @E,002D,BTCS,C=01,A=0016A4001589,T=01,B=00,R=00,S=00

Query peer address

(<<) /btqpa,c=1

(>>) @R,0020,/BTQPA,0000,A=0016A4001589,T=00

Query RSSI

(<<) /btqss,a=58a0238ed80b

(>>) @R,0011,/BTQSS,0502,R=00

You can also send a disconnect command

(<<) /btdis,c=1

(>>) @R,000C,/BTDIS,0000

(>>) @E,0012,BTDIS,C=01,R=0000

To send data in this mode use

(<<) .spps,c=1,d=4C6169726420436F6E6E6563746976697479 

(>>) @R,0010,.SPPS,0000,C=01

Where c = the connection handle and d = is the outgoing payload in hex

When receiving data in this mode you will see

(>>) @E,0016,.SPPD,C=01,D=4D61726B

where c is the connection handle and d is the incoming data in hex

 When plugged into a Windows PC the Vela IF820 DVK will show two comports in Windows device manager.

One com port is a regular UART com port that can be used with EZ-Serial and the other is a HCI com port for flashing firmware.

If its not clear which com port is which you can use Windows device manager. Identify the com ports, right click, select properties and go to the details tab. select the bus reported device description property from the drop down menu.

If the value contains UART0 then this is the HCI com port.

If the value contains UART1 then this is the regular UART com port.

See IF820 DVK SETUP section in the Software User Guide for more information.

Does the Vela IF820 Series - Bluetooth 5.2 Dual-Mode Modules support LE Coded Phy?

Unfortunately not but it does support 2M Phy.

Laird Connectivity is committed to the long-term supply of all its standard embedded wireless modules and packaged products. Laird Connectivity’s products are specifically designed to meet the needs of the industrial and medical markets, which typically require 7 – 10 years product lifecycle. Although Laird Connectivity can’t guarantee that a component used in our products will not be obsoleted and cannot be reasonably substituted, Laird Connectivity can assure customers we will continue to sell our product when we have customer demand and can obtain the necessary components to build our products.

View our full policy here.