> For the complete documentation index, see [llms.txt](https://docs.ifreeq.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ifreeq.com/faqs/device-development/untitled-2/ble-chip-sdk-single-point.md).

# BLE Chip SDK(single point)

## What is the DP point CCR8 used for the door opening method during the development of door locks?

The specific algorithm of CRC8 is: CRC8=CRC16 (hardware type, member id, frozen state) & 0xFF. For the specific algorithm of CRC16, please refer to the source code in the door lock SDK: uint16\_t crc16\_compute(uint8\_t \* p\_data, uint16\_t size, uint16\_t \* p\_crc).

## Bluetooth door lock SDK integration, how to modify the uuid, arch\_key and mac in the firmware program?

Key is the auth-key in the program, UUID is device\_ID, h\_id can be ignored