Questions tagged [decoder]
A decoder is an electronic signal processing circuit, which takes as an input a binary number, and turns on a corresponding pin accordingly. It takes `n` inputs (which can all be either on or off) and outputs `2^n` outputs of which exactly one is on
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Decoding possible UART [closed]
I'm working on an e-bike, and I'm trying to decode possible UART signals (RX, TX, VCC, GND, DL).
I captured some byte values using an Arduino Uno R3 on the TX wire from the controller and got the ...
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Line decoder output changes when the initial clock value changes
I have been trying to code a fm0 decoder. Since the incoming data changes at both negedge and posedge of the CLK, to successfully decode the data, I need to sample the incoming data at the middle of ...
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Does this Verilog HDL code of a decoder look strange in any way?
I am wondering if it is ok to use output instead of wire for another output in Verilog coding (using Quartus for this). Just ...
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Why is memory addressed using 2 address decoders only and not more? [duplicate]
I am currently taking a university course about computer architecture in which we learned basic DRAM architecture and addressing. As far as I know, each latch is selected using decoder outputs to ...
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Decoding Bit Rate Information for an LED Project Using a Logic Analyzer
I am currently working on a project where I'm trying to understand and decode the bit rate information being sent to an LED. I purchased an LED for my backyard that can be changed to different colors ...
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Understanding decode stage of x86 fetch-decode-execute pipeline and its (lack of) register requirements
FDE pipeline has register requirements for the F & D stages: For fetching an instruction from memory, the instruction pointer register points to the memory location of the next instruction to be ...
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How to display 2-digits data using two 7447 decoder?
I have designed a circuit to display the 2-digits data using two 7447 decoder. The design is shown below.
I have two outputs, O1 and O2. O1 represents the ones digit while O2 represents the tenths ...
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24VAC Binary Encoder / Decoder for Sprinkler System
I have a typical sprinkler system that runs on 24VAC.
My sprinkler controller is in my garage and my sprinkler valves are across the yard with a cable running underground with 5 wires. One wire is the ...
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Decoding Soil Moisture Sensor 433 MHz
I need to decode soil moisture sensor using RXB6 and ESP32. I tried several libraries; it can get data but not the correct one. Due to my knowledge on this 433 MHz radio, I can't figure out.
There's a ...
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Why is my 7-segment display not working when output modules (O3-O0) are connected to BCD to HEX converter module?
I have used an 8051 interfaced with an 8255 taking inputs from port A and port 1 and showing the output from port B AND C of the 8255. I also made a decoder for BCD to HEX (0-F). The input value is ...
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What are the considerations of using a common anode 7-segment display over a common cathode?
Common anode:
Do I need resistors here? Where would I connect them?
Common cathode:
Common anode seems simpler circuit wise - but I like the idea that "1" represents "ON" that ...
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Connecting a 7-segment display to a CD4543B decoder
I would like some help connecting a 7-segment display to a CD4543B decoder according to the instructions in the image at the bottom, and get the display to show the expected numbers. How is it ...
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Which of the following input binary conditions will produce an ambiguous state in the flip flop?
For ambiguous state, both outputs x and y must be zero(for active low) to be considered invalid i.e. of both PRESET and CLR are logic "0". Now, analysing the circuit, $$ x=a \oplus D_0 $$
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Weird enable pins 74LV138D
The 74LV138D is a low-voltage 3 to 8 binary decoder.
It has 3 enable pins, one for each of the inputs.
However, two of them are active high, and one is active low... Why on earth would they not pick ...
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Is BCD to 7 segment display a decoder or a driver?
In my book it specifically says that for decoders only one output is high for combinations of each input. And also the number of outputs are 2 power of number of inputs. None of these are true for BCD ...
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What does this function table mean?
This table, part of the SN74LS138 datasheet, explains how inputs relate to outputs:
However, I'm no electrical engineer and I don't understand the bit I've circled in red which says \$\small\mathrm{\...
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How to post various register updates from FPGA to CPU?
I hope this is not too broad a question, I try to be as specific as I can. I am using a Zynq SoC with FPGA and CPU. I am using the FPGA for a lot of DSP, that depends on many register values. In most ...
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Identifying Protocol Using a Logic Analyzer
I used a logic analyzer to read the data line from a small camera battery and would like to understand the authentication my camera is doing to the battery over the one data line. Is there any way to ...
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Need help regarding BCD to 7-segment decoder
I am fairly new to digital logic designing and I need some help in regards to finding a BCD to 7 segment decoder on software. I am using proteus for my counter, and for some reason I am unable to make ...
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7-segment display decoder truth table
I am trying to make a decoder that can display all alphabetical letters on a 7-segment display. My inputs are ABCDE and the outputs are abcdefg
Is this the correct truth table for a circuit? If yes, ...
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TVP5150 output 0x80,0x10 and input video signal not locked
This is my first question, I hope everything is ok :)
I have been struggling with a problem for a while now. I have a PAL camera (from which I barely have any information) connected to a TVP5150AM1 IC ...
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TinkerCAD 7-Segment Display Not Showing on Simulation
I am only on my 5th week trying out TinkerCAD for our Logic Circuits course. We are tasked to create a 7-Segment Display Using Logic Gates only. I did all the boolean expressions needed for each ...
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Reading angular velocity from multiple rotary encoders
I am working on a project, where I need to get reliable data from 4 incremental rotary encoders. The motors can spin at a maximum of 100 RPM, with 420 pulses per revolution. This makes a single ...
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Wireless real-time control of RGB led strip using PWM and RF
I would like to send three 8-bit PWM values (generated using an ESP32 and the ledc library) wirelessly in real-time.
From what I've come across, RF seems like a good option, however I would prefer not ...
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Creating a simple address and data bus with Arduino Uno as a master using 3-state buffers and decoders
First of all, sorry if my post is too general. If you know a better place for this post please let me know.
Problem
I have 5 motors to be controlled independently (but not simultaneously, i.e. one ...
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Latch the values generated by a 4-16 line decoder
I am using a 4 to 16 line decoder to convert a 4 bit number from arduino/seeed/ESP32 to drive circuits like RGB leds which would otherwise use up all my pins. There are some problems with this ...
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Arduino - Inverting Common-Anode 7 Segment Display with a Transistor
I am currently struggling a lot with a tedious issue - I have to control my 7-segment display with a CD4511 decoder. However, my display is Common Anode, and it is not changable in my case. The best I ...
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2-to-4 demultiplexer/decoder active HIGH IC
I'm looking for an IC that takes a signal and sends it to one of four possible outputs. So I came across a 2-to-4 demultiplexer which does just that. 74139 series to be precise. However, they all ...
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computation bit error as sum(abs)
I am working on a realisation the convolutional encoder/decoder with constraint length K=7. Encoder and decoder were implemented and currently I am testing these functions
My test file looks like:
<...
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How decode serial data stream
I am trying to decode a data stream. This signal comes out of an STC 8H1K16 micro-controller. It is from the pin labeled TxD is the picture.
When I trigger the signal I am trying to understand I get ...
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Memory Mapping Table
I am a begginer in the field of microcomputers and their architecture and recently I got an assignment with the following instructions:
With the use of the mapping table find out which adresses in ...
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7-segment display communication
I have attempted to solve this problem making kmaps for the binary counter, mux and decoder however I'm getting stuck on the making them all talk to each other bit, I am using a ATmega32L and a ...
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Why do decoders have a reverse current when the output voltage is high?
So I am designing a pcb using a STM32 microcontroller and I wanted to expand the output pins in order to add a sensor. So I thought of using a 2-to-4 decoder in order to 'add' 2 pins. However, when ...
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What is a post decoder?
I have heard a bit about pre decoders and post decoders recently in circuit design. When I saw the circuits, the pre decoder is same as the normal decoder in every textbook or website. But I haven't ...
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How to minimize microcode complexity in 8-bit home-brew CPU
tldr; I built and later extended Ben Eaters 8-bit breadboard computer. After the initial build I integrated 16-bit program counter and memory address registers, redesigned the instruction set and ...
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3 Bit Counter w/ 7 Segment Display Starts at 111 instead of 000
The goal for this task is to have a 7 segment display output my last name the first two initials of my first name. The output should be FURMANHE with F being the 000 state and 111 being the E state. ...
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Design 3-to-8 decoder with enable using three 2-to-4 decoders and eight AND gates
I want to design a 3 to 8 decoder with enable using three 2 to 4 decoders without enable and eight AND gates. How can I design it? I thought about it, but only 2 to 8 decoder comes out. I don’t know ...
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Simple 7 segment decoder circuit not working
I used a cd-4511 decoder for my seven segment display circuit. It was a simple circuit, just to get familiar with how the 7 segment display and the decoder operate. However, upon sliding the switches, ...
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Bus contention when addressing tristate buffers by decoder output
I'm currently redesigning the signal propagation algorithm of a circuit simulator I'm developing as a hobby project (https://www.antarescircuit.io).
In the new design, I'm trying to detect when ...
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Why doesn't this circuit simulation work?
I am trying to build a circuit using only encoders and decoders. This circuit will output the 1’s complement of 3 bit number. (For example: If I give it 010 it will give output 101.)
I used a ...
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Industry Standard for Memory Address Decoder Design
I am currently designing the address decoder of a piece of ReRAM that will be sent to TSMC and manufactured. I have studied in class and textbook that there are two common address decoder designs. One ...
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Help identifying encoding scheme for RF device
I have this RF encoder that I am trying to customize with an MCU. The remote control device uses an encoder called HS2260. I believe it is a clone of PT2262 device. I was able to get the waveform but ...
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Clarification of "strobe pin" 4-bit latch/4 to 16 line decoder
I'm wondering if I can get a specific behavior out of this chip. I have read the data sheet and am having some trouble understanding the usage of the Strobe pin.
CD4515BM96 Datasheet PDF
USE CASE
I'm ...
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Is there a IC to decode Johnson code to BCD 8421 or 7-segment? [closed]
I'm studying Johnson counter and want to display the counting on a 7-segment display. Is there an IC to decode Johnson code to BCD 8421 or directly to a 7-segment displays?
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Verilog code for construction of 4x16 decoder using 3x8 decoder [closed]
This is my 3x8 verilog module:
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What is the main difference between a decoder and a demultiplexer
What is the difference between a decoder and a demultiplexer and why would you choose one over the other in a design?
Apart from the fact that they are constructed and operated differently, they both ...
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Decoder Simulation Results are incorrect
I was trying to design a simple address decoder using VHDL. The simulation results are wrong. I am sharing the code below for your reference.
In my design, I want to set a bit in my output ...
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Efficient single cycle huffman decoding technique with wider input data?
I have a wider input data (Byte width) running in my system, and I'm implementing a huffman decoding on this incoming data. Since, the Huffman encoded words don't have the fixed length, hence I need ...
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Difference between IC 74LS47 and 7446N
What are the major differences between these two ICs 74LS47 and 7446N whose working is mostly the same ?
Both are used as BCD to 7 segment decoder driver
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Found a particular chip, now I can't find it again
A couple of weeks ago, I stumbled on a particular chip. At the time I didn't need it, but now I do and I can't find it again.
The chip was a 4-16 line demultiplexer, but its input came from an I2C ...