in this tutorial, I am showing how to build a seven-segment display clock
Things needed
- 4* common anode seven segment displays https://amzn.to/3aDfwtP
- Arduino UNOhttps://amzn.to/2VXJOlO
- 3 push buttons https://amzn.to/2KxexB8
- Ds1307 rtc module https://amzn.to/2zmkG0p
- Common PCB https://amzn.to/3cPaNXP
- 2*leds https://amzn.to/2VSgkWB
As the name indicates seven segment displays has 7 segments. each segment is a single led and all the 7 LEDs connected together with a common pin that may be a common positive or a common negative and arranged in a specific style.
A typical 7 segment display has 10 pins arranged in top and bottom each of middle pins are common pins
And others are to control corresponding seven segments
Circuit diagram
we have 4 displays that is totals of 4*8=32 pins to control this our Arduino doesn’t have 32 pins so how to do this. yes, multiplexing…
so we connect all segments together that is segment A of 4 displays together, segment B of all displays together and soo on …
now we have 7 common segment pins and 4 common anode pins that is total 11 pins
yes our Arduino has 11 pins .by using multiplexing lets control 4 displays with 11 pins instead of 32
connections
I connected everything according to the circuit
connect one end of 3 push buttons together and connect to A0, A1, A2
RTCmodule works on i2c communication so connect
SDA TO A4
SCL TO A5
GND TO GND
VCC TO 5V
REPLACING THE ARDUINO UNO WITH HOMEMADE ARDUINO
to save some space I replaced Arduino with my diy Arduino
Hi,
Great tutorial, thank you. The link for the code is broken, any chance you could fix this please
Great work.
it works thanks, also please suggest changes to make it a 12 hr clock i.e am/pm.
will try