CD54/74HC, CD54/74HCT High-Speed CMOS Logic 3- to 8-Line Decoder/. Demultiplexer Inverting and Noninverting. [ /Title. (CD HC,. CD The M74HC is a high speed CMOS 3 to 8 line decoder. There are three binary select inputs (A, B, and C) which determine which one of the eight outputs (Y. 74HC Datasheet, 74HC 3 to 8 Line Decoder/Demultiplexer Datasheet, buy 74HC
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Our output devices will be LEDs.
Without any pushbutton being pressed, all the LEDs are off. To each of these we connect an LED and a series-limiting resistor.
To 74gc238 of these pins, we connect a pull-down resistor. To these pins, we connect an LED along with a series-limiting resistor to limit excess current to the LEDs, so they don’t get blown out. We connect these pins to digital pins 2, 3, and 4.
How to Connect a 74HC 3-to-8 Decoder/Demultiplexer to an Arduino
We will now explain the hardware connections. So it functions as a output port expander. 74ch238 we push down on the first 2 pushbuttons attached to A0 and A1, this gives a value of to the address registers.
This completes the powering that’s necessary for the 74HC But once you do, it’s very simple and straightforward to work.
How to Connect a 74HC238 3-to-8 Decoder to an Arduino
Without any pushbutton being pressed, all the LEDs are off. The rest of the pins, Y0 to Y7, are the output pins. The A0, A1, and A2 pins are the address pins.
Then it repeats back from the beginning. The datasheet for this chip can be found at the following link: So if we have an address pin connected to ground, it has a value of 0.
The rest of the pins, Y0 to Y7, are the output pins. So if we have an address pin connected to ground, it has a value of 0. So if all address pins are connected to ground, this gives a value of These are the pins which are used to control the outputs of the chip. It follows a binary-to-decimal code. The next 3 pins are the enable pins, E1E2and E3. To each of these we connect an LED and a series-limiting resistor.
Using 3 pins, called the address pins, we can create a total of 8 different outputs. This is because we are writing to them with the arduino, not reading from them. This is the equivalent in decimal of 3, so the first 3 LEDs turn on.
If we press down on the pushbuttons, the corresponding LEDs will turn on in a binary-to-decimal format. In this project, we will show how a 74HC decoder works and how we can manually control it with 3 pushbuttons.
How to Build a 74HC 3-to-8 Decoder/Demultiplexer Circuit
After this, in our setup function, we declare these address pins as outputs. If the address pins have a value ofthis equates to the first LED being on. So if all address pins are HIGH, this equates to a value ofwhich in decimal is 7. These address pins control which output pins turn on.
If the address pins have a value ofthis equates to all 7 LEDs being being on. The address pins are kind of the center of control.
So it functions as an output port expander. This equates to all the outputs LEDs being off. The datasheet for this 7h4c238 can be found at the following link: So, again, with 3 pins, we can control 8 outputs. If the address pins have a value ofthis equates to the first 6 LEDs being on. So they are declared outputs. So when the address pins are5 LEDs will be on. 47hc238 the 74HC address 74hc2238 are outputs to the arduino.
If we push down on the first 2 pushbuttons attached to A0 and A1, this gives a value of to the address registers.
It is a 8-pin chip. After this, we have our loop function. And this how the address pins can affect all 7hc238 outputs. With just 3 pins on the microcontroller being used, it adds 8 outputs.
But a 74HC is a very useful chip that has a lot of 74c238. And this is how a decoder chip works to give a microcontroller extra output ports and increased ease of controlling outputs.
The rest of the pins, Y0 to Y7, are outputs.
These address pins control which output pins turn on.