Arduino Tutorial #3 - Shift Registers (74HC595)

[@kitcat2449]

Thank you. My own teacher explained this poorly. As a beginner I want to know exactly what is happening. You're a life saver.

[@FlevasGR]

The simplest tutorial on the internet for shift registers! I used it with my Attiny85 chip. Few notes: while programing the attiny with the arduino as ISP you will end up with a common pin between the arduino and the shift register pin. While transfering the code the chip might reset but there is no need to disconnect it

[@Enigma758]

12:00 with 180 ohm current limiting resistors on the LEDs, you are pulling around 28mA per output which far exceeds the maximum chip current allotment for the 74HC595 which is 70mA according to the datasheet.

[@TizzyT455]

I have wondered what working with an arduino was like and your videos have shown me that is actually quite simple (programming wise) I am probably going to have to learn more about the different ICs etc though but thanks a lot.

[@Sorarse]

Thanks for the video. I am just starting with my Arduino, and want to learn about shift registers. I understand the principle of what they can do, but yours is the first video I have found that explains simply with a demonstration of how the data is transferred from the Arduino to the register.

[@qwarlockz8017]

Hey REALLY nice a clear tutorial explaining Shift Registers. Thanks!

[@VladRomanov89]

thank you sir!

[@qwarlockz8017]

Oh no ... thank YOU! I am sort if putting my brain together to do a 3D cube. Sort of need these cool ideas for that... and bloody fun way to learn cool toys!

[@dosteehemin7177]

Thank you, this video was clean and planned but as a beginner, you used terms that I couldn't immediately understand and continued the video using them. I wish you explained them before you started the programming, like what a latch or clock was, as that would have made it much easier but overall a great tutorial. Well done.

[@wobblebot]

Am I the only one that got really bothered for a really long time when he wrote (STCP_pin_HIGH)

[@icydee1]

+Wobblebot no, that bothered me too. also, did you notice that he did a loop 0 to 8 (nine values) into a register array of size 8? (classic overflow error)

[@wormbros]

Lol

[@thelastcitadel8959]

no that triggered my OCD so badly.

[@hansbraggaar8300]

I very much like your clear and COMPLETE presentation. Thanks a lot

[@typheous99]

Good tutorial. Was looking for something simple but comprehensive. Good work.

[@Metralon]

In the schematic the resistors are in between the chip and the (+) side of the LED. But in the actual circuit the resistors sit in between the ground and (-) side of the LED.

[@wolftalk594]

thankyou so much this is so helpful! ib=ve been trying for a week to get this! thank you so much!

[@vladimirstrulev8501]

Hi Vlad. Vlad here ;-) Thank you very much for all your videos. They are very useful and informative.

[@khawthongxiang2348]

the STCP_pin and SHCP_pin in the code has to be reversed in order to make it work, but overall its a nice tutorial !

[@harrytsang1501]

While the approach demonstrated here is correct, it is also slow due to the use of digitalWrite. The built-in digitalWrite of arduino are known to be slow (~170 clock cycles) because it looks up the port to set every time during runtime. There are libraries such as digitalWriteFast that uses C macros and direct port manipulation that can speed it up to 2-4 clock cycles per write. If you are using Arduino Nano, you can also try to flash the firmware of Arduino UNO so that you have access to more memory. The pinouts are the same and only the firmware is different.

[@p0jnx]

Thanks for the detailed video. I'd like to point out a couple of mistakes in it so that you can notify your viewers, the second for in the loop method has a ++ iterator when i think it was meant to be -- since you're iterating down from 8 to 0. Another problem is that the resistors on the graphical diagram you drew do not match your actual setup, by this i mean that in the diagram the resistors were placed between the output and the + of the leds while in the actual setup you have the resistors between the - of the led and grnd.

[@iconbylvergara6188]

There's something wrong with your code in the video. You switched the SHCP_pin to STCP_pin in the writereg() function. And in the second for loop in the void loop sub, you wrote i++ instead of i--

[@drjwilber]

as with p sark - when you mess up can be hardware / software / or both snoty howard little had problem his cade - asked for help. Solved the problem then of little ability wanted to be superior - tread on others that they no use - to brag about it. Such that little got 25% pay increase - typical of brits and their military contracts Solved other problems - with howard little denigrating my rep and ability brit military can stick it up their pipe as get 'treated' same way as howard little , Its for other countries - where I get paid

[@SamReidland]

Nice tutorial. Your schematic shows the resisters on the anode, but your implementation has it on the cathode

[@raymccoy9105]

Scanning comments looking for references. I noticed it too.

[@stevenvanhulle7242]

Declaring your I/O pins as int is a bad habit. You're declaring them as variables, which they aren't, but as variables they consume RAM. It's better to write #define STCP_pin 9

[@Chopy61]

Just wanted to know, is it only for STCP or also the other pins?

[@OpenGL4ever]

@Chopy 61 It's usually for all pins with one very rare exception. This exception can be, if you want to change the pin during runtime, in this case you will need a variable to store the change. But i don't know a situation where this is needed. So you usually won't need variables for pins.

[@andrewscott1253]

I don't think its a bad habit unless you are writing a program that pushes the limits of the memory. Having named values aids readability which is an especially good habit to teach beginners. Plus, if you use that pin more than about 10 times in code and later want to change that pin, this makes maintenance easy.

[@muppetpaster]

@@andrewscott1253 Memory use when not needed is ALWAYS a bad habit

[@andrewscott1253]

@@muppetpaster It used to be I'll give you that.

[@Engineer9736]

I have a separate power supply meant for the shift register ic, but when i unplug it i notice that the shift register + all the LED's just keep running, probably from energy from the data pins. This is something to be careful with if you're going to put 200 LED's on it. Possibly the total current draw will end up on the data pins of the arduino, blowing them up. I think a resistor between the arduino and the shift register is a good idea to prevent this. Allowing a max of 5mA per data pin should be good enough i think, lower would be better if you're doing more things with the arduino. But good tutorial, i got it working within 15 minutes :D And the LED's response very rapidly which is perfect.

[@geirhansen4371]

Nice tutorial. The breadboard obviously works, but the schematic shows the resistors going to the IC and the LEDs going to ground.

[@alexdempster6782]

only 5 of my LED's are working all at different brightnesses. Also they are not oscillating? could you give me any advice as to why. Thanks

[@P5ark]

Hey I think you messed up SHCP and STCP. maybe your cables are switched. but you have to pull storage LOW outside the loop and the clock LOW and HIGH inside the loop for every bit.

[@drjwilber]

that - with next on software - if messed up finding where a 'pain' tutorial on hardware output with resistor divider as analogue input four inputs with ADS 1115 - texas do not have that and they make the device

[@andysar11]

Can we program the LEDs in such a way that one led glows once 24 hrs and the next glows on next day and so on...

[@Codebyakshay]

Hey by this tutorial i can also access the P4 led matrix or P10 led matrix

[@dl8cy]

near dummy proof tutorial - thank you!

[@PabloPazosGutierrez]

I really like your arduino videos, thanks!

[@anonymousreally9022]

Cool. But have a question. when I saw this and before I got to the fritz in schematic I was wondering where will the power come from to light the LEDs. I didn't thing a single pin could provide enough power to run 8 LEDs at once. Using a 2.2v forward voltage avg for LEDs that's 16+volts of drop.

[@XavierAmado]

Both the for loops in the loop() function are wrong, they are probably trashing the stack, and could lead to issues with a more complex program. The registers array is of size 8, so the conditions should be (int i = 0; i < 8; i++) and (int i = 7; i > 0; i--). This last > 0 should also be >= instead to mimic the HIGH behaviour, in the video the first LED never goes LOW. Other than that, great explanation of shift registers. Thanks!

[@muhammadrafiqulislamkhan6994]

I enjoy your code and project. Thanks for sharing.

[@DrHaifisch]

use the SPI interface and it will go faster, just conect 74hc595 data in to mosi pin, manualy toggle the strope pin and clk to clk pins

[@SatyajitRoy2048]

Your code is buggy. Array is a zero based index and that's why your LED0 was not turning off. Moreover, you have written at location beyond the allocated memory space for the register array.

[@jeffryvergara2301]

Hi I have a question because in my output the LED only blinks once but stay ON all the time. but i reviewed the code but its the same of what you did. Please help. Thanks

[@chaos-ivy]

Very good tutorial. Other than a few code oopsies (most of which have been solved in the description - such as messing up the STCP and SHCP pins) the tutorial was very good. I played with this for a lot longer after, changing the sequences to do some funky stuff. Very happy!

[@willemOO3]

What do I do wrong? I've checked the program on typo's multiple times but can't find any. I get following error message: Invalid types 'boolean{aka bool}[int]' for array subscript exit status 1 Who can help?

[@gtechnics7487]

hello if i run this arduino program then it works but the time between on and off the led's is too long your file with the arduino code in it i can't open could you maybe send this again

[@Inquire98]

"Thank You", thank you very much. That was a REALLY good video...

[@dancluderay1304]

Really like this Video. Would be interesting to see a vs 2015 raspberry pi 2 version

[@hariris9944]

i think that in the code you have a mistake , STCP is the RCLK and must be out of the for loop in the writereg function.

[@Sixstrings63]

Thanks, one of the best shift register tutorials out there and the code works great.

[@erykschubert]

I have a problem. I did everything what you did, but only 4 LEDs light. I don't know where the problem is and how to light up 4 other LEDs...

[@VladRomanov89]

Well, based on the fact that you're able to get 4 LEDs working, I would assume that your issue is in the code. Verify that you are setting the right bits in the program by outputting the status to the Serial port. Without having your circuit in front of me, it's hard to say what's wrong exactly, but I would start there.

[@erykschubert]

EEEnthusiast Thanks for the answer. The problem was with grounding. There should be two grounding cables on both sides of the resistors. I don't know why it works in your example with only one grounding cable going from the line of resistors.

[@serhioromano]

What did you use to create that schematic with arduino board and chip?

[@kawshiklakhani8547]

Could you please explain how the 3d Led Cube works?

[@VladRomanov89]

I've added a link to the correct Arduino Code which I have used for one shift register as well as two of them. I have also created a video tutorial on how to hook up two of them in series. The video will be released this monday. Thanks, Vlad

[@VladRomanov89]

Link to code: staticjolt.com/shift-registers-arduino-tutorial/

[@dj505Gaming]

EEEnthusiast The link just opens up a text-only page full of random characters...

[@VladRomanov89]

***** Yeah... I think some one hacked my WordPress install. I'll have to correct that after the holidays. Sorry about that.

[@dj505Gaming]

Oh yeah... I heard about a massive wordpress hack on the news the other day. Not kidding, either.

[@23vpatel]

program for this where can i find

[@JorgeLuis-po5uq]

Does the arduino work without programing in the breadboard

[@mdsalman971]

i am using MG87FE52AE this ic to weighing scale PCB so i wanted extra display from the board. And that board have 6digit 7segment 16pin so i wanted to convert 16pin to 6 pin by using IN74HC595AN IC. So please i request you to send data diagram ho to connect that ic or is there possible to connect that ic or is your support to that ic? Please give me a answer please

[@fpvrcstuff]

Very well explained tutorial , and code . I'm just learning about Arduino and coding Thank You For Sharing !

[@christophergomez8682]

the first three LEDs connected to Q0 Q1 and Q2 are not lighting up for me even though everything is connected as in the diagram, can anyone explain why?

[@BenMDepew]

is the 74HC595 the same as the 74HC595N. Im a noob in ICs.

[@EwoutJP]

Good work there, gonna order some 74HC595 since I need to power 65 little lights. and on other projects I always need more pins then the arduino's have so... enough reasons to add this comment to your video...

[@DupczacyBawol]

Datasheet for 595 says that maximum VCC current can not exceed 70mA. 8 lit LEDs + 180R = ~ 130mA. So the chip can be easily damaged in your case. Be wise.

[@DesertVox]

Can't you just power the shift register with a 3V source and skip the 8 current-limiting resistors?

[@melgambaseck7288]

Nice guide. I would like to create the same effect with 8 independent situations using the “if” function. It should go like this: situation is true LED 1 turns On. Situation 2 is true LED 2 turns On and LED 1 is still On. Situation 3 is true LED 3 turns On while LEDs 1,2 still On. So I create fill increase or decrease effect. But my problem is that the LEDs keep running On and Off in the loop while satisfying each consecutive situation. How to keep them from running On and Off while ruining the tests for 8 states? Thanks for your guidance.

[@melgambaseck7288]

Note: I use arguing Uno and the shiftOut function...

[@ramanunnikrishnan7354]

SIR I WOULD LIKE TO KNOW IF A SHIFT REGISTER IS PRESENT IN THE ARDUINO BOARD FOR CONNECTING ALL THE PINS OF PWM AND ANALOG ?

[@thesunexpress]

In the interest of completeness, the staticjolt.com website has been down for some time now. Is there any chance the code can be re-uploaded elsewhere? The pinned comment to the Google Docs link also indicates it is either dead and/or defunct code... As is the case for the NXP link, altho Google-fu will readily provide an adequate substitute.

[@Maher-]

Is there a way to control only 1 output EXP( Q4) in the shift register to do a task other than on and off an LED?

[@4mb127]

Why use a resistor for each LED? Wouldn't just one resistor for all of them work? Or did I miss it?

[@paparoysworkshop]

+4mb127 The problem is that the diodes all have different characteristics. One might conduct just a little bit more then the next one so this can cause the diodes to have different brightness. This can lead to one diode failing and then it would take the others down with it. Giving each diode its own resister prevents the characteristics of one diode affecting the others. Using one resistor will often work with no problems and I have done it myself on occasion, but its bad design practice.

[@przewrotnick]

Is it necessary to set stcp to low in order to pass i values to ds? Can't stcp always be set to high? Same question regarding shcp. Sorry for this very down to earth question. I have only once had Arduino in my hands.

[@VladRomanov89]

You do have to pull them low and high. The whole concept of this IC is that it will only trigger when those pins are transitioned. Check out the datasheet, it explains all the details.

[@rafaelmarroquin4429]

I like the video man, really useful

[@tmc200527]

Nice tutorial. I'll have to try that circuit out. What software do you use to draw the pictorial like schematics with the Arduino Board in it? Also have you noticed that KZbin inserts your own blank comments under your own videos. That happens to my new videos. I wonder if that is a clitch?

[@VladRomanov89]

The one in this particular video I just found on Google, but usually I use Fritzing; here is a link: fritzing.org/ they have several tools to help you make schematics and even pcb layouts with Arduino already included. I believe that the blank comment appears because of the share on Google+. When you upload a video, there are checkboxes for Google+, Facebook and Twitter. I think if you remove the Google+ one you should not have a comment appear.

[@kelvinlee5762]

Very Good demo, easy follow.

[@mayurthacker]

Can i use it for analogue outputs ??

[@VladRomanov89]

yes, you can PWM all the outputs if timed correctly. You would have to write a fairly intricate function

[@mayurthacker]

But i have doubt that, when i will switch to next channel of all /8 of chip 595 ... will it memorize & maintain the last defined output till next update !!!

[@001marselle]

mayur thacker it depend on the bits you sent it like if you send 10001000 then in the next turn you send 11110000 it will update all the bits .

[@davidflynn9039]

i dont know what mine one cascade they go on once but wont loop

[@thechriskelly12]

+EEEnthusiast could I replace the LED's with MOSFET's or relays?

[@karthikeyanvaradarajan222]

Yes

[@technikfreaksmj5321]

the link for the program does not work

[@kayrizob92]

Is it possible to incorporate pwm while setting data? What would be needed?

[@Sasch600xt]

Thank you very much !!! You do a great job and helped me a lot

[@linuxguy1199]

Nice vid but can I take inputs from the shift reg and send them to the arduino

[@VladRomanov89]

Jeremiah, you would not be able to do that with this IC. You would need to look for an IC which captures multiple inputs which you can retrieve with Arduino over a communication protocol such as SPI or I2C

[@linuxguy1199]

EEEnthusiast ok thx

[@manuelarmas196]

hello, I need make a led´s cube but Idon´t understand the 74HC595 with arduino,How do I can do? is mandatory to use matrices and vectors. Help please

[@tianlun2001]

But my led seems to go only one direction using your code. Are the resistors important? I didn't put any though.

[@Skandawin78]

I'm trying to use my old 25 key keyboard using arduino. how many shift registers 74hc595n should I use and what is a scan matrix?

[@KymoDoke]

Is it possible to expand the script (and how?) to manage 2 shift registers and then to control 16 LEDs?

[@VladRomanov89]

Definitely! I covered just that in one of my recent tutorials on shift registers. Check it out.

[@tommushrom5929]

just join the ICs in series using the Q pin a output and connecting ot to Din pin on the next shift register. And so on.

[@TDMFAN]

Do as Tom said, then I assume you would adjust the for loops to range from 0 to 15 (i.e. for(int i = 15; i >= 0; i--) and for(int i = 0; i

[@Computertechlighthouse]

Can you help me to converting this: DS_Pin equals to data or clock or latch? STCP_pin equals to data or clock or latch? SHCP_pin equals to data or clock or latch?

[@Cross8ow]

DS= [D]ata [S]torage - data STCP= [ST]orage [C]lock [P]in latch SHCP= [SH]ift register [C]lock [P]in clock

[@bartuu91]

Can I simply connect 3rd party 5V power supply to the breadboard instead of Arduino 5V and GND or there would be a need for some extra protection?

[@VladRomanov89]

+Bartek Boczar You can absolutely connect a 3rd party power supply to the breadboard. One thing to remember is to always connect the GNDs together. This will eliminate the possibility of floating voltages which can cause unpredictable results. However, if you are driving isolated loads, you don't even need to do that.

[@maartenbeute6742]

This was very explaining, thanks

[@jose3538]

How would you write this code in python? I'm just curious

[@sergio95000]

hey i need some help, i'm using 16 leds and 2 Shift Registers (74HC595), but i don't have any idea how to make the software for that, can you help me with that??

[@MrTimm69]

Is there a differnce between the 74HC595 and the SN74HC595, for how i see it the look the same but it is not working :(

[@VladRomanov89]

+Tim Zegers It shouldn't be any different, SN specifies that it is a Texas Instruments IC.

[@SometimesImaPenguin]

Is it upside down/are the pins in the right order but on the wrong side of the chip?

[@vvnnful]

make sure you placed the IC the right way. There is a 'U' like looking dent to identify on one side

[@tommylux247]

I am following another tutorial, showing the LEDs on the reverse for SN74HC595, the notch in the same direction..

[@killerskull1]

hey how can i change the code so that instead of supplying the serial data internal of the arduino, I want to use another source. I have another device thats sending serial data, i want to feed that digital serial data into my arduino and have it send to the shifter to get converted to parallel data. PS. is there anyway to convert the serial data into parallel data right in the arduino

[@infinitemindsetnow]

because of the fact that every single arduino tutorial involving shift registers in existence shows how you can control various leds with a "for loop" or similar, i am going to assume that you cannot individually control leds as needed.Such as when a user "presses button 1 and led 1 turns on" Can I assume that is true?

[@SzeliZoltan]

+David Arroyo Well you assume wrong. If you do not set the bits of the array in a for loop, you can manually set any of the bits to the desired state, then call writereg(). It's just easier to fill the array in a loop and it's adequate for the purposes of the tutorial. If you want to see a code, here it is how to set only the second led to light up: for(int i = 0; i

[@VladRomanov89]

+Zoltán Szeli To be fair, that would still iterate through the shift register through the for loop inside the writereg() function. The answer to the original question is that a shift register is essentially a queue. This means that you can only shift into it and whatever is at the end, falls off. You can use any code you like, but if you want pin 2 to turn ON, you need to first shift a HIGH into pin 0, then shift it over to pin 1 then shift it over to pin 2.

[@rajkkapadia]

Can I get output between 0000 0000 to 1111 1111 range..? If yes then explain please.

[@VladRomanov89]

You can get any output you desire, you just need to shift LOW and HIGH voltage levels you want into the shift register. You can easily set the data to be 01010101 if you wanted to. Watch the tutorial one more time; you can use the same function to input any output combination into it.

[@rajkkapadia]

Thanks man. I appreciate that, I will watch it again.

[@Le_Trinity]

Can I use this 74HC595 IC to control servos instead of led's.. if so what changes needs to be done to the circuit, thanks

[@VladRomanov89]

I would not recommend shift registers for PWM controlled devices such as servos. You can very easily toggle a DC motor with them, but PWM will be a challenge. There are dedicated ICs you can use for those applications.

[@Le_Trinity]

Can you maybe give me a shematic or circuit for this

[@Le_Trinity]

Thanks for your reply

[@Heavengreen1996]

Can you access the ques separately? Or there is only one time delay ?

[@TheFunkman]

very clear. Well done thanks!

[@thelastcitadel8959]

This is a good tutorial. I was wondering if you would know why when i hook this to and 8x8 led matrix for columns and set the rows to ground it does randoms line for a few seconds then just turns on all the led's.

[@arloc1283]

error: 'writereg' was not declared in this scope writereg();

[@daisym6503]

Sir, I'm currently using 24 LEDs and 3 shift registers. When I enter the value 1 to the data argument for the ShiftOut function, the first LED connected to each shift register lights up. Then, when I give the value 255, all 24 LEDs gets lit. Would you please tell me how to only light up 1 LED from the last shift register ? Thank you

[@rengstrom]

I'm looking for a shift register that supports both parallell input as well as parallell output. Is that possible to do with the 74HC595?

[@Loundre3]

No. But an 74HC194 is fit for the task, if your not bothered by it only having 4bits per chip. www.ti.com/product/CD74HC194?keyMatch=74HC194&tisearch=Search-EN-Everything

[@transformer12kv]

the wrong is in last line . for(int i = 8; i>0; i--) not i++

[@trhosking]

Should be for (int i = 7; i >= 0; i- ) ...

[@itslife56]

Is it possible to use a shift register with the analog pins?

[@VladRomanov89]

The analog pins on Arduino can be set to digital, so yes you can use it on them.

[@korbanomalley7002]

For me it just turned each individual LED on and left them on. Any idea what is wrong?

[@VladRomanov89]

That tells me that all your outputs are high. One issue may be the fact that your delay is too short, so you are cycling through them faster than the naked eye can see and thus they appear all lit up. Try sending nothing to the IC and just leave it powered, do the LEDs still turn on?

[@korbanomalley7002]

EEEnthusiast I copied the code exactly as shown in the video

[@ravzir]

Korban OMalley The same thing happens to me. I even corrected that line were the i++ was instead of i-- and the same... what is happening???

[@sethmolson]

EEEnthusiast same here, the LEDs blink up then stay on instead of blinking back down

[@VladRomanov89]

I did make a mistake in the code. apologies for that.

[@AlexanderStoinis]

idk if any answered/asked this yet...could this be applied for analog inputs?

[@athulsnair6498]

Can you make a video for 74HC165 and how to write a code for it(there are already a lot of videos of 74HC165 , but the codes are so confusing)?

[@smksore6266]

How to program if we use 2 register And led 1-8 control by first potensio and led 9-18 control by second potensio Pleas help me

[@smksore6266]

I mean 2 register hc595

[@NathanPhippsONeill]

Should there be i-- in the second for loop?

[@hackertomobile]

Can you create this video with 74hc165 and serial input Arduino numbers ?

[@candleburning]

I'm wondering if it's possible to overload this chip running LEDs. If I understand correctly an LED may draw up to 20 mA of current or 160 mA for eight LEDs. The datasheet for the 74HC595 states continuous current through Vcc or GND should not exceed 70 mA. While the example works I'm still wondering if this is technically outside the chip spec. Does the chip get warm if you light all eight LEDs for a few minutes. Thanks.

[@VladRomanov89]

+candleburning You have the option to trigger transistors from each pin which you would use for each LED. A MOSFET can be triggered by a very low current, so you would avoid this problem. In my example, I used resistances to run the LEDs at about 5mA, so it was fine.

[@kguna74]

hi there, can you please explain your code and how it works. Why you used boolean and writereg, void writereg ? I am a newbie to Arduino, cant find the tutorial on writereg and void writereg. All I know is void setup, void loop! :) Many thanks.

[@ricardogirao7676]

Alguém poderia me ajudar com a seguinte dificuldade que tive usando 74HC595: - Ao ligar o circuito ocorre um pico onde todas as porta ficam em HIGH, minha aplicação é uma Relay Boardm, então ao ligar todos os relés são acionados? - A segunda dúvida é se posso dividir as portas do 74hc595 entre Entrada/Input e Saída/Output, pois na minha aplicação preciso de acionar 4 relés e ler 4 botões através do arduino? ficarei imensamente grato se puderem me ajudar.