"If you have a Bluetooth 1.2 scanning device, you will be able to use
interlaced inquiry scan on it (HCI_write_inquiry_scan_type interlaced).
This has the same effect. In fact, it works better than switching
trains on the inquirer because inquiry is quite inefficient and losing
frames on a particular train can have a big impact on the likelihood of
finding a device.

Of course, this requires the other end to co-operate, so there's not a
lot you can do on the inquiring side."

Can you explain it more and how can i use interlaced inquiry scan on a Bluetooth 1.2 scanning device (HCI_write_inquiry_scan_type interlaced). are there any online reference that i can refer to.? =)