Problem: There is a broadcast but the connection cannot be established;
The following is the troubleshooting work that has been done:
1. The physical layer parameters were measured and no obvious abnormalities were found;
2. After exchanging Bluetooth chips with a fully functional key, it was found that the problem was following the chip. After exchanging, the original board could work normally, but the new key's board could not work properly;
3. The firmware of the key has been verified for a long time and there have been no similar issues at present;
In summary, it is currently necessary to investigate the issue with the chip itself through the original factory protocol.
Please help analyze the reason