WIZwiki-W7500 board with built-in W7500 chip has built-in ARM Cortex-M0 and can use many peripherals such as SPI, I2C, UART, and GPIO. Supporting peripheral devices can be used to control external devices, and network communication is also possible using the built-in TCP/IP core.


STEP 1. Display OLED by using W7500 I2C interface

I would like to introduce the basic method for setup by using the W7500 peripherals, and I will show you how to operate the OLED by using the WIZwiki-W7500 board I2C interface with built-in W7500.



STEP 2. Materials

2-1. WIZwiki-W7500 board


(More details,

Where to purchase:

2-2. LAN Cable

2-3. USB Mini Type-B cable

2-4. Jump wire x4

2-5. Mbed Online Compiler

2-6. adafruit ssd1306 128*64 OLED

2-7. Breadboard


STEP 3. Make!

3-1. Join Mbed membership


3-2. Application code import


3-3. Hardware connection

Ps. Connect the USB cable and supply power to the WIZwiki-W7500 board after completing the OLED connection.



3-4. Download Compile to W7500

Click the Compile button at the top of the compiler



Save and open the folder after completing the compilation.


Drag & drop bin files to DAPLINK

STEP 4. Code


Include header files to use source code and OLED.

Set the I2C pin and input the basic information of the OLED.

Before you start a timer, set the minute and second.

In order to operate the OLED, set up the OLED with the begin function, and output the “Hello World”.

The Wait function keeps the OLED output for one second.


Enter the user application in the While.

Adjust the text size and clear the display.

Make time: minute: second to be output and incremented every second.


STEP 5. Let’s Run!

Press the Reset button to run the downloaded code.




You can easily create and download projects without any other compiler if you use the Mbed Web Compiler. The WIZwiki-W7500 board makes it easy to control OLED, and we have created a timer that can represent hours, minutes and seconds. You can add a switch to create a stopwatch or take the current time info. via network communication and display the real time rather than the simple timer.




Curator: DKay