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Whenever I press the clock button I get all of the leds on except maybe one or two, with some flashing during the button press. I have added a debounce circuit, but still to avail.
Without this buffering, your switch should not work on a button push, only on a release. Get into the habit now.
Finally, you should not count on TTL outputs driving high, as you have shown. TTL works much better pulling loads down. So your outputs should be connected like. Datw may object that this will provide LEDs which are on when the output is low, and off when the outputs are high, which is confusing.
In that case, invert the signals going to your LEDs. Since you already need one section of aand there are 6 gates per IC, you simply go.
Home Questions Tags Users Unanswered. That’s probably causing as much counrer as no debounce was. I’d reduce that down to something in the nF to 1uF range.
Oh, Ill change that and see what happens. So your outputs should be connected like simulate this circuit — Schematic created using CircuitLab You may object that this will provide LEDs which are on when the output is low, and off when the outputs are high, which is counrer. Since you already need one section of aand there are 6 gates per IC, you simply go simulate this circuit. WhatRoughBeast 49k 2 28 Okay I wired 7,9, and 10 together and then connected them to a 1K resistor to 5V. Then I used a pullup resistor for the clear switch.
I switched the LEDs around and connected their input to 5V and their ground to the output pins. I’m still getting the same effect.
4-bit Synchronous Counter with Asynchronous Clear
Also, have you added a 0. I added a 0.
It’s always the simple things. For a circuit board with a ground plane, the usual guideline is at least one cap per 5 ICs. For breadboards, dqta a cap for each IC. You can often get away with less, but as you’ve just learned, insufficient decoupling can have weird symptoms.
N 4-bit counter not counting properly – Electrical Engineering Stack Exchange
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