How to Use OpenSegment Serial Display - 20mm (Green): Examples, Pinouts, and Specs

The OpenSegment Serial Display - 20mm (Green) is a versatile and easy-to-use seven-segment LED display module designed for displaying numeric and certain alphanumeric characters. Its bright green LEDs ensure good visibility in a variety of lighting conditions. This display is commonly used in digital clocks, timers, counters, and other projects where numerical data needs to be presented to the user.

• Digital clocks and timers
• Counters and scoreboards
• Temperature or other environmental parameter displays
• User interfaces for various electronic projects

• Display Color: Green
• Number of Digits: 4
• Digit Height: 20mm
• Operating Voltage: 3.3V to 7V
• Maximum Current: 160mA at 5V
• Communication: Serial (TTL) at 9600 or 19200 bps

1. Power Connection: Connect the VCC pin to a 3.3V to 7V power supply and the GND pin to the ground of your circuit.
2. Serial Connection: Connect the RX pin to the TX pin of your microcontroller, such as an Arduino UNO.
3. Initialization: Set up the serial communication on your microcontroller to match the baud rate of the display (default 9600 bps).

• Ensure that the power supply voltage does not exceed the maximum rating of 7V.
• Avoid driving the display at its maximum current for extended periods to prevent overheating.
• When using with a microcontroller, ensure that the serial communication settings match the display's requirements.

#include <SoftwareSerial.h>

// Create a software serial port on pins 10 (RX) and 11 (TX)
SoftwareSerial openSegmentSerial(10, 11); // RX, TX

void setup() {
  // Start the software serial port at the baud rate of the display
  openSegmentSerial.begin(9600);
}

void loop() {
  // Send a command to clear the display
  openSegmentSerial.write(0x76); // Clear display command
  
  // Display a number with a decimal point
  openSegmentSerial.print("12.34");
  
  // Wait for 5 seconds
  delay(5000);
  
  // Display a different number
  openSegmentSerial.print("5678");
  
  // Wait for another 5 seconds
  delay(5000);
}

Note: The above code assumes that the display is set to the default baud rate of 9600 bps. If the baud rate has been changed, update the openSegmentSerial.begin(9600); line with the correct baud rate.

• Display Not Lighting Up: Check the power connections and ensure that the supply voltage is within the specified range.
• Garbled or Incorrect Characters: Verify that the baud rate of the microcontroller's serial port matches the display's baud rate.
• Display Flickering: Ensure that the power supply is stable and can provide sufficient current.

• Double-check all connections, especially the serial connection between the display and the microcontroller.
• If you're experiencing communication issues, try using a different baud rate or check for any serial port conflicts.
• For any persistent issues, consult the manufacturer's datasheet and support forums.

Q: Can I use this display with a 3.3V microcontroller? A: Yes, the display can be powered with 3.3V, making it compatible with 3.3V microcontrollers.

Q: How do I change the baud rate of the display? A: The baud rate can typically be changed through a series of commands sent to the display. Refer to the manufacturer's datasheet for the specific commands.

Q: Can I display letters as well as numbers? A: Yes, the display can show certain alphanumeric characters. Refer to the character set in the manufacturer's datasheet for supported characters.