rtl8723ds default settings:
H5 protocol
Flow Control on
parity even
internal 32k clock
Host cts need connected to ground
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install bluetooth blueman bluez bluez-tools rfkill libbluetooth-dev
sudo vi /etc/modules
add hci_uart in last line
reboot
lsmod | grep hci_uart
sudo make install
sudo rtk_hciattach -n -s 115200 ttyUSB0 rtk_h5
you can change ttyUSB0 set-up depends on different requirements