DIY ESP8266 Minimum System Development Board - Breadboard NodeMCU

ESP8266 is a SOC (System On Chip) released by the Espressif Systems. This small chip can be used to establish wireless communication. It is a low cost wifi SOC with built in TCP/IP networking software. ESP12-E is manufactured using a ESP8266 chip or ESP8266EX chip. It has 16 GPIO pins. NodeMCU is a development board manufactured by using a ESP 12-E Chip. When we make DIY projects, NodeMCU is not the best choice for us. We don't need to spend extra value for other components. ESP 12-E chip can work independently, if we are supplying constant 3.3V. Using the ESP 12-E chip is a great choice if you are doing a low cost system. We can use AMS1117 voltage regulator or HT7133 voltage regulators for supply constant 3.3V for the ESP 12-E chip. I am using AMS1117 in this case. If you are using lithium batteries, HT7133 is the best regulator for the case, because it is a LDO - Low dropout voltage regulator. Lithium Battery working voltage is 3.7V - 4.2V. AMS1117 needs at least 4V for supply constant 3.3V. HT7133 even give the output voltage for 3.4V. For uploading the firmware/code, we need a USB to Serial converter or USB to UART converter. We can separate the programmer (USB to Serial converter or USB to UART converter) after a successful flashing. You can solder ESP 12-E CHIP on a PCB or PCB prototype board. I have used a low cost PCB prototype board for the DIY project. This project requires a good soldering experience to solder paths to the PCB Prototype board. The maximum input voltage of the AMS1117 is 15V. Make sure to power up this project with a power supply which supply less than 15 volts.

I am using Arduino IDE as my development environment. You can use ESP IDF directly.

ESP12-E chip - 1

USB to UART converter - 1

AMS1117 - 1

10uf - 2

5.6K ohms resistor - 3

100 ohms resistor - 1

3mm led -1

male to male header - 1

First we need to solder the ESP 12-E chip to the PCB Prototype board. Each component should solder without any unwanted solder links. Here I used male jumper headers for the power supply and programming interface (Rx and Tx).

Boot mode selection is the important thing when selecting UART mode or Flash Boot mode. We need to pull down the GPIO 0 to flash the ESP 12-E chip. Then we can pull up the GPIO 0 and execute the uploaded code. This is clearly mentioned in the ESP 12-E datasheet! I am attaching an image of that section. You can also refer to the datasheet for more specifications.

Now you need to connect a USB to UART converter to the diy development board to upload the firmware/code. Make sure to pull down the GPIO 0 by using a jumper cable.

After finishing the upload you can change the jumper to the other side (Pull up the GPIO 0). Now you can do any project like on nodemcu. You can add more components and modules to this board.