LCD cursor positioning in Arduino - Step-by-Step Execution

Concept Flow - LCD cursor positioning

Start

↓

Initialize LCD

↓

Set Cursor Position (col, row)

↓

Print Text at Cursor

↓

End

The program starts by initializing the LCD, then sets the cursor to a specific column and row before printing text there.

Execution Sample

Arduino

lcd.begin(16, 2);
lcd.setCursor(4, 1);
lcd.print("Hi!");

This code sets up a 16x2 LCD, moves the cursor to column 4, row 1, and prints 'Hi!' at that position.

Execution Table

Step	Action	Cursor Position (col,row)	Output on LCD
1	lcd.begin(16, 2)	(0,0)	LCD cleared, ready
2	lcd.setCursor(4, 1)	(4,1)	Cursor moved to col 4, row 1
3	lcd.print("Hi!")	(6,1)	'Hi!' appears starting at col 4, row 1
4	End of code	(6,1)	Final display with 'Hi!' at row 1, col 4

💡 Code ends after printing 'Hi!' at the specified cursor position.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
Cursor Position	(0,0)	(0,0)	(4,1)	(6,1)	(6,1)
LCD Display	"" (empty)	Cleared	Cleared	" Hi" on row 1	" Hi" on row 1

Key Moments - 2 Insights

Why does the cursor position change after printing 'Hi!'?

Because lcd.print() moves the cursor forward by the number of characters printed, as shown in step 3 of the execution_table.

What happens if you set the cursor outside the LCD size?

The cursor will not move correctly or text may not appear; the lcd.setCursor() expects column and row within the LCD dimensions, as initialized in step 1.

Visual Quiz - 3 Questions

Look at the execution_table, what is the cursor position after step 2?

A (0,0)

B (4,1)

C (6,1)

D (1,4)

💡 Hint

Check the 'Cursor Position' column in row for step 2 in execution_table.

At which step does the LCD display show 'Hi!'?

A Step 3

B Step 2

C Step 1

D Step 4

💡 Hint

Look at the 'Output on LCD' column in execution_table rows.

If you change lcd.setCursor(4, 1) to lcd.setCursor(0, 0), where will 'Hi!' appear?

A At column 4, row 1

B At column 6, row 1

C At column 0, row 0

D It will not appear

💡 Hint

Refer to how lcd.setCursor sets the starting position before printing in execution_table step 2.

Concept Snapshot

lcd.begin(cols, rows) initializes the LCD size.
lcd.setCursor(col, row) moves the cursor to a position.
lcd.print(text) prints text starting at cursor and moves cursor forward.
Cursor position is zero-based: col 0 is leftmost, row 0 is top.
Setting cursor outside bounds causes no visible output.
Use these to control where text appears on the LCD.

Full Transcript

This example shows how to position the cursor on an LCD using Arduino code. First, the LCD is initialized with lcd.begin(16, 2) for a 16 columns by 2 rows display. The cursor is then moved to column 4, row 1 using lcd.setCursor(4, 1). When lcd.print("Hi!") runs, it prints the text starting at that cursor position and moves the cursor forward by the length of the text. The execution table tracks these steps, showing cursor positions and LCD output after each action. Key points include understanding that the cursor moves after printing and that positions are zero-based. The visual quiz tests understanding of cursor positions and output locations. The snapshot summarizes the commands and their effects for quick reference.