Datasheet

2 / 23
Other pins used by Bluetooth UART module:
1.
PIO8 is used to control LED indicating the status. It will blink after power on. Different
blink intervals are used to indicate different status.
2. PIO9 is used to control LED indicating paring. It will be steady on when paring is
successful.
3. PIO11 is used to switch the working mode. High level-> AT command mode; Floating or
low level-> normal transparent data mode.
4. The module has built-in power on reset circuitry.