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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40 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 ...
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1answer
36 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
106 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
49 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 ...
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3answers
358 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? ...
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1answer
75 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
votes
2answers
137 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 ...
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2answers
94 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 ...
0
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1answer
79 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 ...
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1answer
33 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
votes
2answers
114 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
126 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 ...
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1answer
88 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 ...
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2answers
69 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
vote
3answers
133 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 ...
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1answer
138 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
145 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 ...
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1answer
190 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
261 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 ...
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2answers
85 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 ...
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1answer
115 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
74 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
66 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
349 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, ...
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2answers
146 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
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1answer
277 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 ...
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0answers
92 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
100 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
70 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
382 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
votes
4answers
219 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) ...
0
votes
1answer
125 views

Shift register m74hc165 connection

I am following the following tutorial (http://www.arduino.cc/en/Tutorial/ShiftIn) to connect a shift-in register to my Arduino. In the tutorial they use a CD4021 'CD4021' shift register and I got a ...
2
votes
1answer
186 views

Is there a difference between TI brand of the 74HC595 and the NXP brand?

I have been trying to figure out the functional differences between TI's version of 74HC595 and NXP's version. I've been looking at the function tables in the datasheet for TI and the datasheet for ...
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1answer
42 views

What is a 3-state storage register on a shift register?

The question lies almost all in the title I have bought a shift register to play with, and looked at the datasheet. I don't understand what is the 3 state storage register associated with RCLK. My ...
1
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2answers
163 views

How to avoid using relays/analog switches in a musical sequencer?

I'm building this: Albeit with a single pulse adding a bit to the shift register when the circuit is powered and another 555 timer (I'll probably use a 556 for both) to provide the clock for the ...
3
votes
1answer
97 views

Alternative to TPST Shift Registers?

So I'm building a musical sequencer that uses a shift register to close relays and pass the discharge pins of three 555 timers through a manual switch and potentiometer (acting as a variable resistor) ...
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2answers
68 views

Inverting shift register [closed]

I am trying to invert the output of a shift register using an open-collector TTL inverter with 33K pull-up resistors. The inverter works fine when input=HIGH, but when the input is LOW, the output is ...
0
votes
1answer
129 views

MC74HC165N + Arduino, Dunno what's the issue

I connected the 74HC165 as per this schematic http://dlnmh9ip6v2uc.cloudfront.net/datasheets/BreakoutBoards/SN74HC165%20Shift-In%20Breakout-v11.pdf and then used this code ...
3
votes
2answers
203 views

Shift Registers Controlling Seven-Segment Display without a Latch?

I'm restoring a Model H Skee-Ball machine, and these old models have a bunch of hardcoded settings and unreliable switch detection, so I want to replace the main control circuitry with something ...
0
votes
1answer
50 views

Best speed/power: daisy chain

I have a project with many buttons and leds. I currently have 2 daisy chains for buttons and each chain has three shift registers (74HC165). I do the same for my leds (STP16CP05) But even with with ...
1
vote
1answer
158 views

How to create traces that don't touch for a four by four non matrix keyboard grid

Hello. I have a potential design for a keyboard whose pcb I will make myself in eagle. This will use cherry mx browns (http://www.cherrycorp.com/english/switches/key/mx.htm for info. Rather than ...
4
votes
1answer
2k views

Arduino TLC5940 and 74HC595

I need to expand Arduino Uno output. After some search I have identified 74HC595 to extend my Digital output and TLC5940 for analog output. I'have also found how to connect them separately to Arduino ...
0
votes
1answer
128 views

max output current on 74LS595 - how to read datasheet

Hi i am a newbie and lack experience on how to read datasheet. basically, I want to find out the max current each pin can supply as I need to connect 8 LEDs to the register. any help would be ...
3
votes
3answers
399 views

Advice… Shift registers, multiplexing, or both

I'm doing a project that has a lot of displays, in the form of single leds or 7-segment displays. So the question is in the title. Using 8 bit registers, if I used them for all the leds, it would take ...
1
vote
1answer
156 views

Shift register parallel in serial out

I'm doing a project in which I will need these and I bought two to learn how to use them and daisy chain them. I'm using the 74HC166, and I'm having some problems. I'm using them according to the ...
2
votes
2answers
213 views

First pin of this SMD chip?

I just bought 74HC595 shift register IC and I'm having trouble finding the first pin. There is no first pin mark anywhere on the chip as you can see below.
0
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1answer
92 views

Transistor system like a shift-register?

I'm new to electronics and need a name for a type of component that I seek. I want to find a component that act as a shift register but with a transistor result rather than the voltage output that ...
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votes
2answers
61 views

sipo not shift reg

i need sipo IC that not shift output not like 74hc164 this wear my output the ic must have internal latch to refresh output at end of last clock sorry for bad English
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3answers
500 views

Driving 12 Seven Segment Displays from an Arduino

I will be using the 14 input/output Arduino. My goal is to create a plane radio console for use with a flight simulator. I am very competent at writing code, but have little knowledge of electrical ...
1
vote
1answer
297 views

Shift register with the Raspberry Pi

I have recently bought some 74HC595N (datasheet) shift registers to play with using my Raspberry Pi. The Raspberry Pi has a general purpose clock that I think I should be able to make use of, however ...