In this experiment, we tried to find out:
1- What is the ESP8266 Wi-Fi module?
2- ESP8266 Pin Configuration
3- How to use the ESP8266 Wi-Fi module without using any other microcontroller.
What is the ESP8266 Wi-Fi module?
The ESP8266 is a low-cost Wi-Fi microchip with full TCP/IP stack and microcontroller capability. It requires power Supply of +3.3V where current Consumption is 100mA and 10uA during the operation and during deep sleep respectively. I/O Voltage is 3.6V (max) and I/O source current is 12mA (max). ESP8266 has a built-in low power 32-bit MCU which operates at 80MHz. It has a 512kB Flash Memory. ESP8266 Wi-Fi module can be used as Station or Access Point or both combined in different IoT applications. Since this module supports serial communication, therefore, it is compatible with many development platforms like Arduino. Arduino IDE or AT-commands or Lua Script are used for programming this powerful module.
ESP8266 Pin Configuration:
Pin Number 1 is named Ground. This pin is used to connect to the ground of the circuit.
Pin Number 2 is named TX or GPIO – 1. This pin is used to connect to the RX pin of programmer/uC to upload program and can act as a general purpose Input/output pin when not used as TX.
Pin Number 3 is named GPIO-2. This pin is used as a general purpose Input/output pin.
Pin Number 4 is named CH_EN This pin is used for Chip enabling – Active high.
Pin Number 5 is named GPIO – 0 or Flash. This pin is used as a general purpose Input/output pin. This pin takes module into serial programming when held low during startup.
Pin Number 6 is named Reset. This pin is used to resets the module.
Pin Number 7 is named RX or GPIO – 3. This pin is used as a general purpose Input/output pin and Can act as a general purpose Input/output pin when not used as RX.
Pin Number 8 is named Vcc, This pin is used to Connect to +3.3V.
How to use the ESP8266 Wi-Fi module without using any other microcontroller.
To connect the ESP8266 to the computer we need a specific adapter. TTY adapter which is a USB Serial can be used for this purpose. But in this study, we used the Arduino Uno as a Bridge to talk with the module directly.
Note: By bypassing everything in the Uno we used it as a bridge. Connect the reset pin on the Arduino Uno to GND to bypass its bootloader.
1 – wired the ESP8266 and Arduino Uno as follows:
- connecting RESET of Uno to GND of Uno (to bypass everything in the Uno)
- connect the TX of ESP8266 to the TX of Uno
- Connect the RX of ESP8266 to the RX of Uno
- GND of ESP8266 to GND of Uno
- VCC and CH_PD of ESP8266 to 5v of Uno
- connect Arduino to the computer
2 – open the Arduino Serial Monitor in the Arduino IDE.
- Choose “Both NL & CL” on
- Adjust the Baud rate on 115200 or 9600.
- Now start to send AT commands as follows:
- To check if it is working type AT in Serial Monitor and get OK response:
- If you get OK, set the WiFi mode as station mode (client) as follows:
- you can list the Wireless AP with the following command:
- Join the network
Congratulations! You connected to the network.