RSSI value no update for several minutes, sometime scan can't work at the same time

Hong Gao

Hello,

We are using TI2564C chip and use HCI command to read RSSI value every second to detect device distance.

We found sometimes the RSSI value is fixed and no updated even we moved BT devices from different distances.

By the way, it also happens that during RSSI detection, the scan BT devices function sometimes doesn't work, the inquiry command is sent out successfully, but no inquiry result reported.

Would you help to check what causes these problem and how to solve them?

The log for RSSI value not change is attached.

Thank you very much.

Regards

Gao Hong

over 5 years ago

0 Hong Gao over 5 years ago

Intellectual 850 points

RSSI_NOchange.rar

0 Hong Gao over 5 years ago in reply to Hong Gao

Intellectual 850 points

Hello,

In the attached latter part of the log, the RSSI value keep to be -63db and not changed for a long time, but the connected iPhone is moving from time to time.

Regards

Gao Hong

0 tscheck over 5 years ago in reply to Hong Gao

TI__Mastermind 23525 points

Are you using the vendor specific HCI command or the standard BT spec version? According to the following thread, the VS command has better precision:

https://e2e.ti.com/support/wireless-connectivity/wifi/f/968/t/785096

Regards,

Travis

0 Hong Gao over 5 years ago in reply to tscheck

Intellectual 850 points

Hello,

We are using HCI_VS_Read_RSSI (0xFDFC) vendor specific command.

For most of the time the value has no problem, but it happens sometime that there is no value update when range is changed.

Regards

Gao Hong

0 Hari Nagalla over 5 years ago in reply to Hong Gao

TI__Mastermind 27080 points

It should normally update every second or so.. It is a back ground process. Did, you try moving away and coming close by?

Thanks

0 Hong Gao over 5 years ago in reply to Hari Nagalla

Intellectual 850 points

Hello,

Yes, the smartphone is moving to different distances near and far, but the value keeps the same for 2-3 minutes.

Regards

Gao Hong

0 Hong Gao over 5 years ago in reply to Hong Gao

Intellectual 850 points

Hello,

Is there any more feedback?

Even with HCI_VS_Read_RSSI (0xFDFC) there is no update for some minutes.

Log is attached.

Please help to check, thanks.

Regards

Gao Hong

Bluetooth®︎

Bluetooth forum

RSSI value no update for several minutes, sometime scan can't work at the same time