OscilloForge — NE555 Astable Frequency & Duty Cycle Analyzer

About this project

OscilloForge is a two-part Electrical Engineering project: the student builds a classic NE555 astable oscillator circuit (R1=10 kΩ fixed, R2=50 kΩ adjustable potentiometer, C=10 µF) and then uses an Arduino Uno to precisely measure and display the resulting frequency, duty cycle, HIGH time, and period on a MAX7219 4-digit 7-segment module. A CHANGE interrupt on Arduino pin 2 captures the 555 output's rising and falling edges using millis() timestamps; dividing 1000 ms by the measured period gives live frequency to four significant figures. Pressing the MODE button cycles through four display modes (Hz → % → HIGH ms → Period ms); a yellow LED wired directly to the 555's output pin blinks visibly at the oscillation rate; green/red LEDs confirm stable-signal and no-signal states; and a HOLD button freezes the reading for lab notes. Students verify their hand-calculated theoretical values (f = 1.44/((R1+2R2)×C), D = (R1+R2)/(R1+2R2)×100%) against real measurements — the core learning objective of every 555 timing-circuit experiment.

What you get

• Complete, commented source code
• Full components list with quantities
• Pin-by-pin wiring guide and connection table
• Step-by-step upload and testing guide
• Project report (.docx, IEEE style)
• Presentation slides (.pptx)