3.3 V serial UART
Connect module TX to host RX and module RX to host TX. Use a shared return and a 3.3 V logic adapter.
HC-06 bridges Classic Bluetooth serial traffic to a local UART. The vendor documented separate master and slave builds.
Module serial data input. Use 3.3 V logic.
| Pin | Signal | Direction | Function |
|---|---|---|---|
| 1 | UART_TX Output | Output | Module serial data output. Connect to the host RX input. |
| 2 | UART_RX Input | Input | Module serial data input. Use 3.3 V logic. |
| 3 | UART_CTS Input | Input | Active-low hardware flow-control input. |
| 4 | UART_RTS Output | Output | Active-low hardware flow-control output. |
| 5 | PCM_CLK Bidirectional | Bidirectional | Serial PCM clock. |
| 6 | PCM_OUT Output | Output | Serial PCM data output. |
| 7 | PCM_IN Input | Input | Serial PCM data input. |
| 8 | PCM_SYNC Bidirectional | Bidirectional | PCM frame synchronization. |
| 9 | AIO0 Bidirectional | Bidirectional | Programmable analog I/O. |
| 10 | AIO1 Bidirectional | Bidirectional | Programmable analog I/O. |
| 11 | RESETB Input | Input | Active-low module reset. |
| 12 | VCC Supply | Supply | Main 3.3 V supply connection. |
| 13 | GND Return | Return | Common return. Connect every GND contact. |
| 14 | 1V8 Regulator rail | Regulator rail | Internal regulator rail. Leave open with the standard 3.3 V supply circuit. |
| 15 | USB_D− Bidirectional | Bidirectional | USB differential data minus. |
| 16 | SPI_CSB Input | Input | Active-low SPI chip select. |
| 17 | SPI_MOSI Input | Input | SPI data input. |
| 18 | SPI_MISO Output | Output | SPI data output. |
| 19 | SPI_CLK Input | Input | SPI clock input. |
| 20 | USB_D+ Bidirectional | Bidirectional | USB differential data plus. |
| 21 | GND Return | Return | Common return. Connect every GND contact. |
| 22 | GND Return | Return | Common return. Connect every GND contact. |
| 23 | PIO0 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 24 | PIO1 Bidirectional | Bidirectional | The reference firmware uses this pad for status LED drive. |
| 25 | PIO2 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 26 | PIO3 Bidirectional | Bidirectional | Wake input on the reference master circuit. |
| 27 | PIO4 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 28 | PIO5 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 29 | PIO6 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 30 | PIO7 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 31 | PIO8 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 32 | PIO9 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 33 | PIO10 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
| 34 | PIO11 Bidirectional | Bidirectional | Programmable I/O. Its application function depends on the installed firmware. |
Connect module TX to host RX and module RX to host TX. Use a shared return and a 3.3 V logic adapter.
| Parameter | Limit | Conditions and source |
|---|---|---|
| Module supply3.1–4.2 V | 3.1–4.2 V | Typical connection is a regulated 3.3 V rail at pad 12. Guangzhou HC HC-06 Module Data Sheet, §§ 2–3 |
| Pairing current30–40 mA | 30–40 mA | Reported by the vendor for the bare radio module. Guangzhou HC HC-06 Module Data Sheet, § 2 |
The pin map covers the Wavesen bare 34-pad module from the April 2011 datasheet. The circuit uses the documented Linvor AT dialect with the radio disconnected.