1. Seven Segment Display

2. What's A 7-Segment Display? A 7-segment display is a package with 7 bar-shaped LEDs arranged to allow the display of many useful digits and some letters. Each segment (labeled A-G) contains an LED which may be individually controlled. DP is an eighth LED, the decimal point.

3. Common cathode means that each segment's cathode is connected to common pins – 3 & 8, allowing the anode of each to be connected to the controller.

4. Activity #1: Building and Testing 7- Segment Display By supplying anodes with Vdd, individual segments can be energized.

5. Displaying the number 3. What segments would be lit to display the number 2 and the letter A?

6. Displaying the number 3. What segments would be lit to display the number 2 and the letter A?

7. Activity #2: Controlling the Display Of course the BASIC Stamp can control Vdd to the segments from the I/O pins.

8. OUTH = %10000100 Sets segments B (P15) and C (P10) to be HIGH (on) and the remainder LOW (off) 0 0 1 0 0 0 0 1 B C The display is a parallel device since multiple lines are used to transmit the bit sequence.

9. 3 input to 8 output decoder E B2 B1 B0 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 0 0 0 0 0 1 1 1 1 1 1 1 0 0 0 1 1 0 1 1 1 1 1 1 0 0 1 0 1 1 0 1 1 1 1 1 0 0 1 1 1 1 1 0 1 1 1 1 0 1 0 0 1 1 1 1 0 1 1 1 0 1 0 1 1 1 1 1 1 0 1 1 0 1 1 0 1 1 1 1 1 1 0 1 0 1 1 1 1 1 1 1 1 1 1 0 1 X X X 1 1 1 1 1 1 1 1 B0 B1 B2 E Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7