A shift register is a cascade of flip flops, sharing the same clock, in which the output of each flip-flop is connected to the "data" input of the next flip-flop in the chain, resulting in a circuit that shifts by one position the "bit array" stored in it

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36 views

How to design shift register using T flip flop [on hold]

I am know D flip flop to T flip by using XOR gate and D flip flop. How to make shift register using T flip flop ?
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1answer
52 views

74hc595n shift register error

I want to put in series 2 74hc595N . I made the schematic from here: When I send a value the first register sends it also to the second one. I have same value on both. I change them (master/slave) ...
0
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0answers
52 views

How to increase number of LED blocks in a moving LED display

I have been working on a project where I have to make an 80x20 sized moving LED display. I'm using a decade counter to shift the characters being displayed. I want to know, in the programming ...
0
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2answers
75 views

Design a 4-bit PISO shift register with 4 DFFs and 3 AND gates

I want to design a 4-bit PISO shift register with 4 DFFs and 3 AND gates. I have gone so far that these two designs can be implemented, but I can't go further minimizing it so as to use 3 AND gates ...
0
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1answer
52 views

Emf interference on arduino and breadboard , using 74HC595 shift register, how to prevent it?

I’m using a 74HC595 chip (shift register) NPX semiconductors, connected to and arduino board. Basically the shift register switches on and off 8 leds in sequence. Everything seem to be working, code ...
0
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2answers
39 views

Building circuit for n-relays using flip flops, is this the best solution?

I'm trying to build a circuit for n relays, each relay should hold it's state (ie latched). My first Idea was to use decoders, but clearly this was a bad option, since the state of the relays won't ...
2
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2answers
260 views

Why is shift register very important?

I learned about shift registers a few weeks ago but I don't know why it is very important and everyone said that it is necessary for microcontroller, etc. Please make sense for me.
0
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1answer
78 views

Increase toggling speed of PNP for PWM

I got a shift register which I use to PWM LEDs. Since I multiplex this toggling I noticed some "afterglowing" if the next LED is not active of the same color. (RGB cathode) Multiplexing by the MOSFET ...
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1answer
220 views

What are Vcc and GND on a shift register?

What are Vcc and GND on a shift register? I thought that I had to provide a positive voltage to the IC via the Vcc, but turns out that I can operate my shift register without powering the Vcc. ...
0
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1answer
40 views

Help designing a serial adder [closed]

I need to build a circuit that adds two n-bit 2's complement numbers. the two numbers have to be stored in shift registers. The circuit should start with the least significant bits of each number and ...
0
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1answer
54 views

FSM for predesignated process (How to draw the state diagram)

let me start by saying this involves some homework problems so if you could help guide me a bit I would greatly appreciate it. I have been working with finite state machines for a bit in my course ...
0
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0answers
47 views

Parallel-in, parallel-out, universal shift register

I am trying build circuit of parallel-in/parallel-out universal shift register. I have found circuit in the Internet. Here it is I have tried to do this using MicroCap , but it doesn't work as ...
0
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4answers
135 views

Shift Register Counter

I am working on a project with my MBED microcontroller and I'm running into some snags, because I'm new to it and getting myself confused with how exactly everything works. I have my MBED hooked up ...
0
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1answer
35 views

Parallel-In-Serial-Out with Parity?

Can someone recommend a shift register IC with integrated parity or CRC generator? Is there such a thing anyway?
0
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1answer
31 views

HCF4021BE usage w/ uC

http://www.datasheetarchive.com/dlmain/Datasheets-30/DSA-599035.pdf The above datasheet is useless to me. (I do know my way around a datasheet somewhat, though) 1) Can someone explain how the heck ...
1
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1answer
91 views

Pull up does not work

I got a breadboard with some logic on it. Including it's own power suppply. It is connected to my Arduino Mega 2560 to fill a shiftregister with some bits. Whenevery my arduino is in a undefind state ...
0
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1answer
29 views

There is no 'latch pin' on MC74HC164A shift register

Unlike a 74HC595, this shift register (http://www.onsemi.com/pub_link/Collateral/MC74HC164A-D.PDF) doesn't have a latch pin. How then do I output the data stored in the registers (to something like an ...
0
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1answer
94 views

Toggle transistors with an shiftregister to light up an LED

First of all I'm quit new to electrical engineering. I had it 3 years in class but I didn't do well. So here is what I plan. I got some shift-registers (74HC595) Which I'll set with an arduino mega ...
0
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0answers
70 views

Unable to keep 2nd shift register in chain of 3 from “leaking”

I am working on a word clock, and I am using 3 shift regsiters (CD4094BE) and 3 darlington transistor arrays (ULN2003A) to control whether or not 21 different words are on or off. The words consist of ...
0
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1answer
64 views

3 State Shift Register with 2-to-1 multiplexers

For a homework assignment I need to Redesign the right-shift register circuit of Figure 12-10 using four D flip-flops with clock enable, four 2-to-1 MUXes, and a single OR gate. The figure ...
0
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1answer
46 views

Issue driving a shift register

I am trying to drive a 74ACT299 shift register with a Microcontroller. Looking at the datasheet I thought it was pretty simple. Set the data bit then pulse the clock, repeat. After I wrote the code, I ...
0
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2answers
149 views

binary number is parallel-loaded into a shift register

A binary number is parallel-loaded into a shift register. The shift register is then commanded to shift right" for one clock pulse. How does the value of the shifted binary number compare to the ...
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3answers
78 views

how can i get parallel data entered into a shift register circuit

If i want to use a shift register circuit to input several binary bits at once (parallel data transfer), and then output the bits one at a time over a single line (serial data transfer). describe how ...
5
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3answers
386 views

Will 74HC595 as LED sink damage LED when pin goes high?

If used as a LED sink, what happens if a 74HC595 pin goes high? Might the LED blow? I expect that when a pin is low, current will sink and the LED will light. What about the opposite condition? ...
0
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1answer
137 views

Simple high side driver for multiplexed 7-segment displays?

How can I best drive and switch high side power (for multiplexing) between the 7 displays with as few components as possible, for under $2. I am trying to simplify a design. I have a custom board ...
3
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2answers
419 views

Sharing Clock and Data for 74HC595 and CD4021B Shift Registers?

Can output shift registers (74HC595) and input shift registers (CD4021B) share the same clock and data lines on Arduino using SPI, with different latch pins "activating" either chain for input or ...
0
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2answers
106 views

Shift registers(?) failing after being left on a while

Resolved: SLCLR on SN74HC595 was not tied to VCC, so behavior was inconsistent. I have a custom built board that is running seven 7-segment displays, multiplexed using SPI from an 5v Arduino Pro ...
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1answer
127 views

problem with LED Matrix circuit

I want to create a LED Matrix circuit with 74HC595 shift register and 2n7000 mosfet. The schematic is as follows. I have mentioned voltage levels at various points. All the control signals of ...
0
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1answer
49 views

Generating a desired pulse train in Xilinx ISE software

Need some help with VHDL and FPGA since I am new to it. I have a Virtex-4 FPGA and I wish to generate a binary pulse train of 16 pulses from FPGA using VHDL programming. My desired pulse train will ...
2
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2answers
204 views

Using the raspberry pi to measure multiple electrical circuits

I am looking to use the raspberry pi to measure the power consumption of multiple household electronics and record the information to analyze later on. However, I'm not sure if it's possible to ...
3
votes
3answers
156 views

Can several CS pins be multiplexed with a shift register?

When sharing a SPI data line between several ICs and an Arduino, what exactly are the frequency constrains of the CS pin? Can I use a shift register to multiplex the CS pins (thus only requiring one ...
1
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1answer
149 views

communicating to shift register with ATmega32 without using given SPI pins

I'm trying to use an ATmega32 to communicate to a MAX7219 chip for multiplexing with an led matrix. However, I do have multiple different devices that I want to communicate with. I am trying to ...
1
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2answers
93 views

Displaying character OSL641501-ARA dot matrix LED

I am learning to control this dot matrix LED (OSL641501-ARA datasheet). I have seen some tutorials on how to control it with 2 shift registers. The problem is I am totally confused with the concept of ...
1
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3answers
151 views

Lower power version of ULN2803?

I want to drive around 80 LEDs from an Arduino with 10 8-bit shift registers. (Some will be RGB LEDs; I count those as 3.) I know of the TPIC6B595 high power shift register but it's expensive: 1.75 ...
1
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1answer
323 views

CD4094BE Arduino problems

I'm trying to build a circuit which uses three 4094's to give me enough outputs to drive a number of LED's. I've built a few similar circuits before in the past using the same code and schematic, but ...
1
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1answer
640 views

PWM driven LED array over a shift register

I am trying to drive 8 LEDs connected to a 74HC595 shift register with PWM. I want to be able to set each LED to a different brightness. The PWM signal is connected ...
0
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1answer
414 views

What are the functions of the ULN2003A and HCF4094 within this circuit?

We are building a wordclock and want to know what the following components do within the circuit: ULN2003A driver IC HCF4094 shift register This is the schematic:
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2answers
507 views

LED driver on 74HC164 - need explanation

I'm building thermometer with long led bargraph (is that correct word?). It will be 60x 0805 LEDs. I want to use low-cost PIC16F1503 microcontroller with just 12 I/O pins. I have few spare 74HC164 ...
0
votes
2answers
90 views

Driving an electromagnet through a shift register? [closed]

I want to know if it is reasonable to use a shift register to control electromagnets. We want to drive electromagnets with about 400-500mA. The TPIC6B595 data sheet claims "Each output provides a ...
1
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1answer
230 views

Help me understand this shift register timing diagram

My basic understanding of using a shift register to convert serial to parallel data is this: On every clock pulse, the state of the serial data pin is read As data is read, it gets shifted in to the ...
1
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1answer
86 views

Using the same clock for multiple shift register

Sorry for the beginner question. I'm working on a nixie tube clock and I have a bunch of shift registers for each tube. Do I need to use a different clock for each IC or can I use the same clock for ...
2
votes
1answer
70 views

What would the firmware to control Shift1 system (for 1-pin shift register operation) look like?

This is a follow on question from this answer by Spehro Pefhany, in which he explains to us how to use 74HC595 serial shift registers with only one digital output pin. Below's the picture he posted. ...
2
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2answers
477 views

How exactly does this shift-register work? - Fairchild 74HC589

I'm using a PISO shift-register, specifically the Fairchild Semiconductor 74HC589. I got the jist of the workings of a generic shift-register via the very useful animated GIF in Wikipedia link above, ...
0
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2answers
222 views

3.3V signals to a shift register IC with a 5V supply

I have an SN74HC595N shift register that I want to have output 5V on the Q outputs. If I power it with 5V on VCC, can I tie the SER, SRCLK, etc. pins directly to the 3.3V digital outputs on my ...
2
votes
1answer
614 views

Johnson Counter VHDL

I have a problem given to me that states: Design a 4-bit Johnson counter and decoding for all eight states using just four flip-flops and eight gates. Your counter needs not be ...
0
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0answers
143 views

Ring counter vhdl

UPDATE: CODE IS FIXED AND CORRECT (AT LEAST I THINK) I am trying to design an 8-bit self correcting ring counter whose states are 11111110, 11111101,.......,01111111. This includes reset and enable ...
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2answers
114 views

How to connect an AND gate with a shift register

I'm new to using flip-flops, and making them into shift registers, but what I'm trying to do is turn on a logical AND gate based off the input of two flip-flops. The scenario is: first, a room light ...
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1answer
96 views

How to clear a 4 bit shift register with no clear input?

I have 4 bit pipo shift register 74ls95 . It does not have an clear input. Is there any way to clear the register without giving all the parallel inputs as zero. I am using it as an component of shift ...
2
votes
2answers
458 views

Using an Arduino to Emulate a CD4021 Shift Register for Controlling an NES [duplicate]

This is probably a silly thing to do when I could wait for my CD4021s (74HC165Ns) to arrive and save myself the hassle but I feel as though this can be done and I'm simply missing something. I've ...
2
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4answers
267 views

250 LED control

I am in the process of designing an automated rock climbing wall that will have 250 monocolor LEDs lit in a predetermined pattern that will be changing every 10 seconds. My controller (actually a PLC) ...