HC-05
schematic, Dimension
Pin definitions
Pin No. Name Type Description
- 1 UART-TX CMOS serial data output output
- 2 UART-RX CMOS input serial data input
- 3 UART-CTS CMOS serial input Clear to Send
- 4 UART-RTS CMOS serial output request
- 5 PCM-CLK bidirectional PCM clock
- 6 PCM-OUT CMOS output PCM data output
- 7 PCM-IN CMOS input PCM data input
- 8 PCM-SYNC bidirectional PCM data synchronization
- 9 AIO (0) two-way programmable analog input and output ports
- 10 AIO (1) two-way programmable analog input and output ports
- 11 RESETB CMOS input Reset / restart button
- 12 3.3V + 3.3V power supply input
- 13 GND Ground Ground
- 14 NC output NC (please vacant)
- 15 USB-DN negative bidirectional USB data
- 16 SPI-CSB CMOS SPI chip select input port
- 17 SPI-MOSI CMOS input SPI data input
- 18 SPI-MISO CMOS output SPI data output
- 19 SPI-CLK CMOS clock input SPI port
- 20 USB-DP bidirectional USB data is being
- 21 GND Ground Ground
- 22 GND Ground Ground
- 23 PIO (0) programmable bidirectional input / output port (0)
- 24 PIO (1) programmable bidirectional input / output port (1)
- 25 PIO (2) programmable bidirectional input / output port (2)
- 26 PIO (3) programmable bidirectional input / output port (3)
- 27 PIO (4) programmable bidirectional input / output port (4)
- 28 PIO (5) programmable bidirectional input / output port (5)
- 29 PIO (6) programmable bidirectional input / output port (6)
- 30 PIO (7) programmable bidirectional input / output port (7)
- 31 PIO (8) output status indication LED port 1
- 32 PIO (9) output port status indication LED 2
- 33 PIO (10) programmable bidirectional input / output port (10)
- 34 PIO (11) input module state switching pin, HIGH -> AT command response to the work of the state; Low or floating -> Bluetooth regular work status.
Main Pin Functions
Pin | Definition | Description |
---|---|---|
1 | TXD | Example |
2 | RXD | Example |
11 | Reset | put it NC, connect to low for reset |
12 | 3.3V | VCC |
13 | GND | GND |
31 | module status | 1hz flashing (when power on)- at command mode 2hz fast flashing = pairing mode |
32 | Pairing status | Output low TTL before pairing, and vice verse |
34 | Mode selection | High TTL for AT commands mode Low TTL for pairing and communication mode |
Set to Master Module
- 1, PIO (11) is set high.
- 2, Power module into the AT command response status.
- 3, HyperTerminal or other serial tool, set the baud rate 38400, 8 data bits, 1 stop bit, no parity, No flow control.
- 4, the serial port to send characters "AT + ROLE = 1 \ r \ n", the successful return of "OK \ r \ n", where \ r \ n is a carriage return line feed.
- 5, PIO (11) is set low, re-power, module-based module, automatically search for slave module to establish a connection.