The diagram below illustrates the high level connections required to drive a single 7-segment display on the scoreboard. The below circuit was repeated 4 times - once for each of the four 7-segment LED displays. Each circuit takes a single data line as its input (C32 outputs T4-T7), and uses a shared clock signal (C32 output T3) that is common to
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all of the 4 LED display circuits. The scoreboard therefore requires 5 pins total on the C32 to operate, along with 5V power, 13. 6V power, and ground. The single input to each 7-segment LED display is not adequate to directly control the operation of the display. To control the segments independently of one another, the scoreboard uses a 74HC164 8-bit serial-in, parallel-out shift register. This particular shift register operates by performing and AND operation on the two input lines and assigning this logical value to the first output pin of the shift register each time a rising edge is detected on the clock input. The value in the first output subsequently shifts to the second output, and so on down the line. By pulsing the clock 8 times, the full set of 74HC164 outputs can be assigned. With 4 data lines and a shared clock pulse, the C32 can simultaneously control the states of 32 different outputs, and completely change their values in 8 clock pulses. The only limitation on the use of the shift registers is the requirement that the output circuitry be functionally insensitive to the transient output states which occur when the contents of the register are being changed. In the case of the LED display, these transient states are manifested as almost imperceptible flickering of individual segments during the refresh process. The choice of a common cathode LED display requires that the individual segments of the LED...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
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In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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