HC-05

From ElectroDragon Wiki

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
2hz slow flashing - communication 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.