Introduction: LED Analog Clock
Designed an LED analog clock using 72 leds, 6 IC4017 decade counters, and two 555 timers. Created a 1Hz frequency clock pulse from the first 555 timer in order to clock two decade counters that drive the the “second hand” LED chaser configuration. The LED chaser uses the green cathode pins of the RGB LEDs and lights up each of the 60 LEDs for one second going from top to bottom, left to right. After the 60th second and last LED is lit, the LED chaser is reset for the next minute. Created a 1/60Hz frequency clock pulse from the second 555 timer in order to clock two decade counters that drive the the “minute hand” LED chaser configuration. Similar to the “second hand” chaser, the "minute hand” chaser uses the blue cathode pin of the RGB LEDs and lights up each of the 60 LEDs for one minute going from top to bottom, left to right. After the 60th minute, the chaser is reset for the next hour and the first IC4017 decade counter for the “hour hand” is clocked. At the end of each hour the decade counter is clocked, and the LED will light for 1 hour until the next clock pulse is received. The 10th hour is anded with the hourly clock pulse to clock the last IC4017 (lighting the LEDs for hours 11 and 12) and on the 12th hour, both of the “hour hand” counters are reset back to 0.
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