Synchronous counter from simple logic

It works as reversable synchronous counter with these states: 0, 3, 6, 1, 4, 7 (shown in binary).

It contains only three J-K fl It works as reversable synchronous counter with these states: 0, 3, 6, 1, 4, 7 (shown in binary).

It contains only three J-K flip-flops and the rest is 12 NAND gates of combination logic.

It consist of two double J-K flip-flops (74HC112, the fourth works with button as clock enable), three quad 2-input NAND gates (74AC00, 4011, 4093), one hex inverter (4049, can be also one more 4x2 NAND; two gates with resistor and capacitor make oscillator for clocking the J-K flip-flops), two buttons (clock enable and direction), CR2032 lithium cell, three LEDs and some resistors and capacitors.

All these fit on one row breadboard :)

For more information visit: http://8b.cz
This project: http://8b.cz/counter.php

Category:

Howto & Style

Tags:

• synchronous
• counter
• ttl
• cmos
• logic

[babykelf]

can i know how did you make the sequence reverse with just a switch?

[Vlakpage]

that's the combination logic, try to look at the schematic, link is in the description

you can play in the simulation with direction button (click the circle) and clock enable

[junit12c]

im in a digital electronics class in my high school and were doing alot of this logic stuff right now and we have a project coming up and our teacher showed us some schematics and it had at least 25 gates...it could be simplified but thats not the point of the project =}... our Digital Electronics calss also just got a national certification thing...i liked ur video

[Vlakpage]

thanks

[paulwoody]

Could you explain to me what a HEX Inverter is? I understand what an Inverter does but what does the HEX Inverter do?

[Vlakpage]

it means 6x inverter, so the are six inverters in one package, often referred as hex inverter (also quad nand is 4 nands in one package)

[abfig78]

Cool Man!! Take a look at my Videos Let me Know What You Think.

[radioam232]

Good work!