Dell Vostro 2520
Broadcom Corp. BCM43142 Bluetooth 4.0
Ubuntu 20.04
Windows 10 Pro
Windows 10 Home
Android 11
iPhone 12
I purchased a mini Bluetooth keyboard for use with my Android phone. Brand unknown but the model number is BK3001; there are hundreds available on eBay, Amazon, etc. This keyboard works with Android 11 on my Xiaomi Redmi Note 9 Pro smartphone, Windows 10 Pro* and Home+, and iPhone. But when on Ubuntu 20.04.x I open the Settings app at Bluetooth and it scans for Bluetooth devices forever without noticing my keyboard, imaginatively named "Bluetooth Keyboard".
After searching AskUbuntu again I tried:
~$ bluetoothctl
Agent registered
[bluetooth]# power on
Changing power on succeeded
[bluetooth]# agent on
Agent is already registered
[bluetooth]# default-agent
Default agent request successful
[bluetooth]# scan on
Discovery started
[bluetooth]#
Again discovery finds nothing. Neither does:
~$ hcitool scan
Scanning ...
~$ bt-device -l
No devices found
Shouldn't Bluetooth Just Work? It has been around for quite a while now but although many other devices can find it, Ubuntu 20.04 can't. Any advice please?
* My wife's Lenovo laptop.
+ Dual-booted into Dell Vostro 2520.
It appears that if the Dell Vostro 2025 is suspended and then awakened later, Bluetooth cannot detect any external Bluetooth devices. So here is how to get the Bluetooth Keyboard BK3001 to pair with Ubuntu 20.04.4 LTS:
* The title-bar menu and Settings > Bluetooth may not synchronise. I have seen one show that Bluetooth is on and the other that it is off. Awakening from sleep also needs to be fixed so that Bluetooth returns to the state is was in before suspension.