@Minho-Lee Appreciate the interest, we just release the customizable FW on Github: Aceinna/openRTK330-lib, together with the platform on Github: platform_aceinna-imu, you will have a GNSS/ins library wrapped with open-source FW. The RTK_INS App on the platform is available in a day or two for you to import from the VS code. Then, you could modify the UART, CAN, SPI and Ethernet interfaces and debug with OpenRTK330LI module.
Please email to firstname.lastname@example.org for later quick response. Thanks.