“This is digital clock using 0.91 inch OLED and arduino pro-mini.
It’s the first time for me to utilize the very small OLED display and tiny pro-min board.
Therefore, simple project is chosen as digital clock making is relatively easy and not much complex.
While making the circuit above, I need to handle several challenges like below.
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- Pro-mini board type is very confusing as 3.3v and 5v type of boards are available
- As pro-mini board lacking USB interface for programming, additional break-out board (USB to serial programmer) is necessary for uploading sketch code
- 0.91 inch OLED is using I2C interface and DS3231 real time clock module also using I2C for communication
- Choosing correct voltage regulator is necessary for power up the clock circuit
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When you using arduino Uno or Micro boards, circuit wiring and uploading program is very easy as there are many how-to contents are available in Internet.
But for the simple project such as clock making, personally thinking that using expensive Uno or micro boards is a kind of luxury. .
That’s why I’m choosing pro-min board as its price is the half of Uno and Micro boards.
But according to the how-to in several web-pages I saw, pro-mini is a little bit special for configuring and using it.
Let’s start story about making digital clock with pro-mini.”