What is the difference between the Ezurio and legacy Bluetooth Xpress (BGX) bootloader you provide for Lyra?

In addition to the standard Ezurio (formerly Laird Connectivity) bootloader for Lyra, our team also released the so called „legacy“ Bluetooth Xpress (BGX) bootloader on our Lyra Firmware GitHub page for compatibility reasons. It is based on the same bootloader configuration as introduced and used by the BGX220 Wireless Xpress modules. This bootloader version is therefore highly recommended for customers with existing Bluetooth Xpress (BGX) hardware designs moving to Lyra.

The main difference between the Ezurio and legacy Bluetooth Xpress (BGX) bootloader is the mapping / location of the BOOT pin. Please see the below table for more details. The BOOT pin is an active-low digital input to force the module into DFU bootloader on reset. It is used to determine when the execution of the bootloader is required, and for example enables updating firmware via the Serial DFU (UART) interface. For this reason, it is very important to verify the BOOT pin against your current hardware design, especially when migrating from a BGX13 or BGX220 module.

Please note that a bootloader for Lyra is required to execute and run applications. By default, all Lyra modules ship pre-programmed with the Ezurio bootloader type. You can replace and update the bootloader at any time, but only via the Serial Wire Debug (SWD) interface.