Special Commands

This page will discuss the Serial 7-Segment Display's special commands:

1. Clear display
2. Cursor control
3. Decimal, colon, and apostrophe control
4. Brightness control
5. Individual segment control
6. Baud rate configuration
7. I2C address configuration
8. Factory reset.

First, a quick breakdown of the commands, their control byte and any data bytes:

Special Command	Command byte	Data byte range
Clear display	0x76	None
Decimal control	0x77	0-127
Cursor control	0x79	0-3
Brightness control	0x7A	0-255
Digit 1 control	0x7B	0-127
Digit 2 control	0x7C	0-127
Digit 3 control	0x7D	0-127
Digit 4 control	0x7E	0-127
Baud rate config	0x7F	0-11
I2C address Config	0x80	1-254
Factory reset	0x80	None

Clear Display

The clear display command performs two functions:

1. Clear the display - all LEDs, including segments and decimal points, are turned off.
2. Reset the cursor to position 1, the left-most digit.

The clear display command byte is 0x76.

There is no data byte, so any displayable data sent after the clear display command will be displayed on digit 1.

Arduino Sample Snippet (Serial Mode): To make the display read 12Ab., we can't be guaranteed that the cursor is at position 1. To ensure that it is, we can use the clear display command before sending our data.

// ... after initializing Serial at the correct baud rate...  
Serial.write(0x76);  // Clear display command, resets cursor
Serial.write(0x01);  // Hex value for 1, will display '1'
Serial.write('2');   // ASCII value for '2', will display '2'
Serial.write(0x0A);  // Hex value for 10, will display 'A'
Serial.write('B');   // ASCII value for 'B', will display 'b'

Note: The clear display command byte value is equivalent to the ASCII value for the 'v' character. This value was chosen because 'v' is not all that displayable on a 7-segment display.

Cursor Control

Decimal, Colon and Apostrophe Control

Brightness Control

Individual Segment Control

Baud Rate Configuration

I2C Address Configuration

Factory Reset