CE 351 Microcontrollers - Fall 2020

Name: Monica Fuson
Email: mrfuson@fortlewis.edu

LEDs and SSDs

Introduction

A seven-segment display consists of light emitting diodes (LEDs) that are connected together to a common pin. By forward biasing the appropriate pins of the LED segments in a particular order, some segments will be lit while others will be dark allowing the desired character pattern of the number to be generated on the display.

In this study, light emitting diodes (LEDs) and seven-segment displays (SSDs) will be used to understand how to use an Arduino Uno & IDE software. Other investigations will include the use of a push button, a decoder, and a shift register to optimize controlling the LEDs and SSDs with less inputs.
Materials and Methods
Arduino Uno controller board
 Resistors (300 ohms, 220 ohms, 1k ohms)
 Decoder (M74HC4543)
 LED lights (assorted colors)
Arduino (IDE) Software Wires Shift Register (74HC595N)
 Push Button

Circuit Board
 SSD (LSHD5503)

Sections 1.1-1.3 & 2.1-2.4 were completed utilizing the LEDs tutorial.
Sections 2.1-2.4 were completed utilizing the SSDs tutorials.
Tutorials: LEDs and SSDs

Results

LEDs
1.1 Blinking On-Board LED

Video 1: On-board LED blinking

1.2 Blinking External LED

Video 2: External LED blinking

1.3 Running LEDs

Video 3: LEDs running in a sequence loop

2.1 Push to Turn On, Release to Turn Off

Video 4: LED controlled by a push button (ON/OFF)

2.2 Push to Turn Off, Release to Turn On

Video 5: LED controlled by a push button (OFF/ON)

2.3 Push to Blink LED

Video 6: LED blinking in sequence after utilizing push button

2.4 Modifications

Figure 1: IDE code to modified section 2.3 (part 1)

Figure 2: IDE code to modified section 2.3 (part 2)


Video 7: LED starts blinking 4 times per second. When utilizing the push button, LED blinks once per second.

SSD
2.1 SSD Powered by Individual Wires

Figure 3: Numbers 0-9 simulated using individual wiring to a SSD

2.2 SSD Powered by Three Wires (decoder)

Figure 4: Numbers 0-9 simulated using a decoder wired to a SSD

2.3 SSD Powered by One Wire (shift register)

Figure 5: IDE code used to program a shift register to control the SSD


Video 8: SSD controlled through serial inputs made to a shift register

2.4 SSD Powered by One Wire (More than one SSD device)

Figure 6: IDE code used to program a shift register to control multiple SSDs

Figure 7: Display of "2019"

Discussion

Each of the sections were successfully completed with Figures 1-7 displaying IDE code and expected results. Videos 1-8 displayed physical results including blinking of LEDs and the SSD running through specified input.