To anyone that has bought Ben's timer kit: the switch provided there is a make-before-break switch, as opposed to a break-before-make! However, there is an easy solution to fix this. Simply invert the logic that the gate in the video uses; i.e.: - Connect the switch's central pin to 5V, not ground - Use pulldown resistors to GND for pins 2 and 4 The rest of the circuit is identical. By inverting the logic, you are essentially converting the make-before-break switch into a break-before-make switch. I have tested this thoroughly and can confirm that with the original circuit and the kit's switch there is bouncing, which is fixed after doing the above method. I hope this might help someone! Thank you, Ben, for the amazing videos!
Does this change the set up in part 4. Because everything I try to connect the 3 555 times to the inverter, and, and or gates it doesn't work. Could you please help me. Thank you.
@@justinsherman9633 Idk how to connect the three pinned, make-before-break switch included in the kit with the 555 timer. This is a different switch from the video.
@@kashyapkhatri2325 where he has the middle pin of the switch ground change that to the 5v and where he has on the 555 timer port 2 and 4 in the five v change to ground. Have the top pin of the switch inrto part 4 of the 555 timer. Pin three into part 2 of the 555 timer (tigger on the schematics.)
For anyone who buys Ben eater's kits, you need to buy "break before make" switches. The included switches are "make before break." This causes the bistable circuit to not debounce at all. Took me a whole week to figure this one out.
Why would it not debounce? Coming from the set to the reset, the initial make before break would have both the set and reset input high. Then the switch would break the set connection leaving reset high. The reset might bounce but this wouldn’t matter as long as those bounces are after the set is broken (which seems logical if the bounces are at the end of the movement not the middle). I don’t have the tools to verify this but it makes sense to me?
I purchased and received my Ben Eater kit today. Going through the tutorials/package the switch is now different. The newly included switch is a "slide switch". In the included printed manual it notes next to the switch that "This replaces the push button toggle switch used in the videos". Just wondering out loud if this change was for the reason pointed out by @TheOverUnder?
One of the core concepts that is hard for folks used to working in analog electronics is the pull-up resistor. Imagine dimming the lights for a romantic evening by turning on the hairdryer. It’s like that…
Just discovered your brilliant videos. I've allegedly learnt this type of thing at college & university but only now do I feel I'm really understanding it. You have been added to a small list of superb UA-cam channels that are changing the way we educate. Thanks.
Break before make and make before break another subdivision of switches...... 4 years of electronics engineering and absolutely nobody in the college ever told me about this... His every video has something new to learn ❤️
I love these 555 1-2-3 part videos, I'm just starting to learn electronics deeper and these videos helped me way lot better than other channels. You're now at 555k Subscribers, and it's a coincidence learning 555 at the same time, lol. Please don't quit making these videos. Best regards,
Just wanted to thank you for this. I decided to try building a computer in Minecraft so I can better understand how they work, so this video series is a godsend. I already got the 555 timer working (though for the actual I'll use a hopper clock) so it was good to understand how they work.
Thank you Ben for your precious work! I have just finished to study all your 44 video ! Everything is perfect made . I didn’t know anything about Fetch or Register or whatever and now I can understand the elementary way a computer works. Thank you! I bought the package to build it , I can’t wait to receive it! 🙏🏻👍🏻
I have yet to view your 555 as timer videos. But I wanted to congratulate you on thinking to post these types of videos for people who seek to learn this stuff. I’ve built the examples and I’ve made use of the crystals just as they’re demonstrated, just as I’ve used my real time clock with the CR2032 button cell battery. I get a strong sensation from seeing the video, that you prefer (or maybe have had more experience with) TTL driven clocks. It now occurs to me that chasing the TTL clock (I guess I’m locked in phase) is the real key to understanding these signal styles that you have so cleanly demonstrated. This is some very important wisdom. It’s the true meat and potatoes for making the decisions regarding circuit design. Also, I can use this to more fully understand hardware design languages like verilog or pshvhdl. Thank you so much your videos have made my 2019 a ‘yippee’ year so far!
01:20 Another idea is to solder it to a DIL socket. 02:18 There's another problem with such a switch: we cannot control the exact moment at which we will switch to the automatically clocked signal. This may be a problem sometimes. So a better idea would be a _single_ clock which can be _advanced_ either manually or automatically depending on the switch's position, so that it would always start an entire new cycle from scratch after switching to the automatic mode, and finalizing the last pulse after switching to the manual mode, but just holding up the next pulse until manually triggering it as a one-shot. That's one of the reasons I was wondering about how to reuse a _single_ 555 chip for this dual purpose.
If you start from the astable multivibrator circuit from the first video, I think it should be possible to add some extra components to be able toggle it between astable and monostable mode. Maybe something like: * A switch to switch the lower trigger input between the capacitor voltage and 5 V - when it's at 5 V, the 555 won't notice that the capacitor voltage is low so it will be stable in the low state. * A button to pull that some lower trigger input high when the switch is in the position for the monostable mode. That should be enough to start one cycle. This scheme should give a bit of debouncing, because it's just manipulating the trigger input, which in turn causes the SR latch to change state. But if you press the button long enough that the high trigger input triggers to reset the latch, I'm not sure what happens. Maybe the button should ground the high trigger input too.
If you can make it so that the extra controls only deactivate the triggers (either the lower or the upper depending on if the button is released or pressed) then you should only be able to slow the cycle down compared to the astable case, which I think is good. And it's if enough if a trigger activates once, so there's your debounce.
Just watched about 2 hrs of your videos in a row and realized I hadn't :thumbsup: any of them, shame on me. So I decided you deserve another subscriber, sub'd. Thank you for you invaluable educational demonstrations. You sir are an extremely good teacher, you deserve every sub you get!
Darn, i was hoping you'd use 2 555s not 3, i have a 556 in my parts bin i've been meaning to use... Maybe half the 556 for the astable, the other half for the bi-stable, and a flip-flop for the mono-stable?
Remove the limiting resistor to the variable R, and add the stepper button in series. That way the “switch” is nothing more than stoping the pulse, and while it’s not pulsing, the push button sends another pulse.
Shouldn’t there be an OR gate between the /reset’s NOT and the thresholds comparator output? Otherwise there could be contention issues in the SR’s R input and current could be sinked to either the comparator or NOT’s outputs (which could presumably damage them)?
In order to reset with Pin 6, you'd need to connect that pin to a voltage above 3.33 V, so probably 5 V. In order to set with Pin 2, you connect it to a voltage below 1.67 V, so probably Ground. But we want to dpdt switch to toggle between set and reset. So Pin 4 is convenient, because you reset with that pin by connecting to Ground. So the switch just toggles whichever pin is connected to Ground.
Amazing videos so far Ben! I'm just having a little trouble with the switch. The LED starts off and when I toggle the switch it turns on, however it doesn't turn off again when I toggle it again. I can fix the issue by unplugging pin 6 on the 555 rather than having it set to ground. FYI setting it to 5v stops it working altogether. Basically I'm wondering if anyone knows why this is and more importantly if I leave 6 on the 555 unplugged will the circuit still work as intended?
Hi Ben. Thank you for an amazing project! Now I am on my way of building it. I have difficulties in programming the microcontroller. Is there any way to contact you and ask the questions? Thank you. Regards
5:30 Can't the switch bounce "all the way back" ? Meaning it might reach S then bounce back to trigger R and back again to S ? In which case the SR latch would provide nothing much.
Furrane no. If you imagine a piece of metal hitting the floor, it will ‘bounce’ a few times before coming to a stop against the floor. This what is happening inside the switch. Now imagine the metal is upright on the door saddle between the hall and the kitchen. Let it fall towards the kitchen and it will bounce a little as it hits the kitchen floor but it won’t bounce enough to double back and bounce on the hall floor.
I think the debouncer, in this case, is useful in very few cases. (in the previous video, it was 100% useful! even though it is random) E.g if you debug and as you said you wait to switch into manual mode when you change to manual, the signal will be 0 on the manual clock (because you don't press it). So from there won't come any extra 1 signals. It could only happen, when you change back from manual to clock and the clock when you change is in 1. Then some quick behaviour could happen, but not at debugging. So that would be less fustrating, I guess :D
Hm, I was unsure about this too, but after some more thinking, I believe that Ben's point stands. Imagine you have a high clock as you switch to step mode. As you slide the switch, just at the boundary of disconnecting the astable timer, contact could be intermittent, thereby potentially causing unwanted clock pulses.
Hello Ben Eater! I was wondering if I may use this circuit for IEEE members at Purdue University Northwest for educational purposes. This covers a lot of important concepts for Electrical Engineers and I’d like to show new students how electronics really work!
Hello. I've noticed that you replaced the electrolytic capacitor with a ceramic disc capacitor. Is it okay to interchanged the two type of capacitors in your usage of them and they will still performe that same function no matter if you interchanged them, or is there a particular reason why you would use an electrolytic capacitor instead of a ceramic disc capacitor or vice versa? There are a couple of different ttype of capacitors such as electrolytic, ceramic disc, tantalum, mylar, etc. out there and I'm wondering if it's okay to use them interchangeably or is it that these capacitors are each use for different applications?
Reviewing this while looking at what I built and I don't have it set up like this at all, even though it works. I have pin 2 going to a 1k resistor to ground (pull down resistor?) and then if the switch is on, then ground is directly connected to pin 2. And yet it works when I flip the switch. Pin 4 has a pull up resistor and connects to the other side of the switch, so that looks right. So I moved the pull "down" resistor to where it should be as a pull up resistor and it still works. It's like pin 2 pulls itself up automatically from the chip. Weird.
Is there anyway to do this kind of thing with Dip Switches instead of just a push button? Curious is there's a way to do this without any soldering, lol
Can someone explain to me how the switch @ around 4:09 where he's showing how the switch normally works? I don't understand how the LEDs turn on there. Thanks!
See, the switch that Ben is using is a 'double throw switch', which has a 'fixed' contact pin(Physically speaking, the pin in the middle of the switch) and a 'variable' contact pin. The fixed contact pin is connected to the 5 V power supply. The 'variable' contact pin switches between 2 connections which in this case, are the 2 LEDs with current limiting resistors connected in series with it. So, when we press the switch, it 'switches' between the 2 LEDs, lighting them up when the respective pin is in contact with the respective LED. I hope you have understood this.
Actually both can damage the LED. Too much voltage will blow the wire attached to the PN silicon, and too much current will melt the wire (inside of the LED). We are playing with power. So your Resistor in series with the LED = ( [(Voltage Source) - (Voltage drop across the LED, or another way of saying it LED Voltage)] / LED current. www.resistorguide.com/pictures/resistors-in-LED-circuits.png See >>> www.resistorguide.com/resistor-for-led/
You can't have too much voltage without too much current for a forward biased diode!! Reverse bias yes you can have too much voltage and cause avalanche failure.
Someone else wrote this fix for that: To anyone that has bought Ben's timer kit: the switch provided there is a make-before-break switch, as opposed to a break-before-make! However, there is an easy solution to fix this. Simply invert the logic that the gate in the video uses; i.e.: - Connect the switch's central pin to 5V, not ground - Use pulldown resistors to GND for pins 2 and 4 The rest of the circuit is identical. By inverting the logic, you are essentially converting the make-before-break switch into a break-before-make switch.
I understand that you wanted to present all those 3 practical use, but I think you could have used just 2 555 times by connecting the sides of the toggle switch to the clock and the naked button, with its base connected to the de-bouncing 555.
Can someone help me please? I connected the circuit in the exact same way as he did but it doesn’t work. When I plug the power in the light is off, but when I press the switch the light comes back on. The problem is that when the light comes back on the switch won’t turn it off again. I’ve tried rebuilding the circuit, pressing the switch multiple times, and using a different switch. Nothing has worked so far. If you have any solutions to this I would appreciate it very much! I'm stuck!
Thanks for the reply. I will try this later on. I have ordered 3 sets of damn switches from america haha! Hopefully what you said will fix it. Thanks again!
Can i use a 3.3KOhm as a pull-up resistor instead of the 1K ones you used? This way i think i could reduce the current draw, if it doesn't mess with 555's internal circuitry.
Holobrine They are all precut and kept off screen for the examples. He has previously sized the wires and shaped them then removed them from the circuit.
Ben, does it matter what type of capacitors you use in a RC circuit? I remember using a lot of electrolytic capacitors for things I built. I remember having a hard time finding the values I needed in any other form. You can tell I use to do a lot of shopping at Radio Shack.
Minefan48 sorry man, I've tried and failed to find a decent one. If I were you I'd just solder some single core wire to each pin on any toggle switch. That's what I've done and it's worked out well so far.
I think the Double-pole toggle switch he is using is the TL2230EEF140 from E-Switch (the EE stands for latching OA would be momentary) It can be found on mouser.com for example if you don't find any in amazon or your local electronics shop
Hi Mr: Ben ,my name is TONNY from Africa I really appreciate your work and I have been watching your videos and they have taught me alot, today I want to you to help me in my project: In this project I have a (HUCULESE INSTICT P8 DJ controller)made in China, This controller works very fine but their is a problem with its CROSSFADER ) The C-fader was made of carbon,and with time when scratching , the carbon gets off quickly then you have to replace it with another new C-fader for every 5months which is very annoying,and as in Africa getting a spare parts sometimes you have to make an order which is very expensive,Now here is where I need your help I bought an Arduino starter kit because of your interesting work,but I still have alot to learn,Now Mr Ben .I want to reprogram this DJ controller such that it can use an optical C-fader system ,I have all the materials for this project but I don't know where to start from like the software for reprogramming the DJ CONTROLLER .So to put it in short I want to remove the (carbon potentialmeter and replace it with optical potentialmeter)how can I get this controller's IDE software like arduino uno and others uses arduino ide plus where do I start from eg : changing the potentialmeter codes to whatever I prefer,
Can someone help me please? I connected the circuit in the exact same way as he did but it doesn’t work. When I plug the power in the light is off, but when I press the switch the light comes back on. The problem is that when the light comes back on the switch won’t turn it off again. I’ve tried rebuilding the circuit, pressing the switch multiple times, and using a different switch. Nothing has worked so far, I think it may be the switch is only single pole. But that wouldn’t make sense because it has three connections that makes it appear as a double pole switch. If anyone can help me it would be appreciated!!
@ 8:24 where you start explaining the breadboard, we see a resistor of also 1k connected to RESET pin, which does not exist in scheme previously, nor RESET appears to be connected to Vcc. Please, correct me. Thank you!
My Bistable Clock just won't work! I've checked the circuit like a million times. Can Someone please help? And is there a replacement for the Bistable Clock?
Wait, so I wanted to order your video parts to build the computer myself. Since I live in Belgium, I wanted to source the parts from here. When looking at your part list, I got stuck on the SPST switch. After almost 2 hours I figured out you are using a dpdt switch. Is this item on the partlist incorrect? I know you are only using one side at a time. Is this why you recomend a spst switch? Great vids btw. Feel like I am learning more than in school.
It does he mentions an spst switch but in his vids he saids dpdt switch I asked above if this is a mistake or a recommendation, since we are only using one side.
where do you pull those resistor values from? why do you use a 1kOhm resistor to pull up pin 2 on the T555? why not 1MOhm? After all you're shorting it to ground for extended periods. Why not 100MOhm? Why not +InfOhm? What are the advantages and disadvantages of different pull up resistor values and how do you decide which one to use? Or do you just pull those values out of your rear end?
For the resistors, LEDs, and such, check DigiKey as their parts are really cheap. ICs and breadboards are more expensive on DigiKey so try finding an electronics surplus store - generally fairly decent prices, and more willing to give you deals if you're buying a lot. I found the ICs needed for the whole project at 1/2 the price they would've been on DigiKey (and without shipping). Also satisfies the "but I want them now" itch, and they can be super fun to browse.
@@jacobtohahn That is what I was trying to say by ironically exaggerating Mateos question about the 556. The whole point of this thing is building it. Of course you could swap the circuit with a 556 but that would kind of be the same as just swapping the whole thing for something pre-build.
i have been looking into the 556 (dual timer) or the 558 (quad timer) to make this clock circuit . it is the same theory and concept just less chips and less space used on the breadboard , with a 558 there is one 1 power pins and 1 ground pins instead of 3 power pins and 3 ground pins (one for each chip) with the 555 timers. i don't have any 558 timers so i am working on making it with a one 555 and one 556. my questions are : is there any down side of using a 556 or a 558 instead of all 555's? are 555's more (or less) reliable than the others? is it likely for each timer to interfere with the others? etc?
I'm sure you could optimize the circuit further by reusing the 2nd 555 timer. With a bit more optimization, you could probably even get away with using a single 555 timer since we don't really need both states to be running at the same time.
3 episodes in and I am getting the vibe that whenever there is a problem, you just add a triple 5.
lol
Styil I have used literally hundreds over the last 20+ years. There’s very little you cannot do with a triple 5.
I really liked the clever use of the SR latch to debounce the switch. Brilliant!
@@kjamison5951 Can I find gf with it?
@@realdragon probably. Show the right girl some creative uses for a 555 and she'll be all over ya
To anyone that has bought Ben's timer kit: the switch provided there is a make-before-break switch, as opposed to a break-before-make! However, there is an easy solution to fix this.
Simply invert the logic that the gate in the video uses; i.e.:
- Connect the switch's central pin to 5V, not ground
- Use pulldown resistors to GND for pins 2 and 4
The rest of the circuit is identical. By inverting the logic, you are essentially converting the make-before-break switch into a break-before-make switch. I have tested this thoroughly and can confirm that with the original circuit and the kit's switch there is bouncing, which is fixed after doing the above method.
I hope this might help someone! Thank you, Ben, for the amazing videos!
Does this change the set up in part 4. Because everything I try to connect the 3 555 times to the inverter, and, and or gates it doesn't work. Could you please help me. Thank you.
Hi there, I am stuck at this part of the module. Can you link an image of your clock or a sketch of your circuit?
Thanks!
@@kashyapkhatri2325 which part? Did you get the three 555 timers to work?
@@justinsherman9633 Idk how to connect the three pinned, make-before-break switch included in the kit with the 555 timer. This is a different switch from the video.
@@kashyapkhatri2325 where he has the middle pin of the switch ground change that to the 5v and where he has on the 555 timer port 2 and 4 in the five v change to ground. Have the top pin of the switch inrto part 4 of the 555 timer. Pin three into part 2 of the 555 timer (tigger on the schematics.)
For anyone who buys Ben eater's kits, you need to buy "break before make" switches. The included switches are "make before break." This causes the bistable circuit to not debounce at all. Took me a whole week to figure this one out.
Thanks, I saw this happening and was confused by it. Just replaced it with a switch from an IKEA clock, haha.
Why would it not debounce? Coming from the set to the reset, the initial make before break would have both the set and reset input high. Then the switch would break the set connection leaving reset high. The reset might bounce but this wouldn’t matter as long as those bounces are after the set is broken (which seems logical if the bounces are at the end of the movement not the middle). I don’t have the tools to verify this but it makes sense to me?
see here for quality discussion on why I was wrong www.reddit.com/r/beneater/comments/ebgk0e/the_555_bistable_will_not_work_with_the_switches/
I purchased and received my Ben Eater kit today. Going through the tutorials/package the switch is now different. The newly included switch is a "slide switch". In the included printed manual it notes next to the switch that "This replaces the push button toggle switch used in the videos". Just wondering out loud if this change was for the reason pointed out by @TheOverUnder?
Shaheen Ghiassy he probably was trying to fix it once he realised
One of the core concepts that is hard for folks used to working in analog electronics is the pull-up resistor. Imagine dimming the lights for a romantic evening by turning on the hairdryer. It’s like that…
Just discovered your brilliant videos. I've allegedly learnt this type of thing at college & university but only now do I feel I'm really understanding it. You have been added to a small list of superb UA-cam channels that are changing the way we educate. Thanks.
Break before make and make before break another subdivision of switches...... 4 years of electronics engineering and absolutely nobody in the college ever told me about this... His every video has something new to learn ❤️
I love these 555 1-2-3 part videos, I'm just starting to learn electronics deeper and these videos helped me way lot better than other channels.
You're now at 555k Subscribers, and it's a coincidence learning 555 at the same time, lol.
Please don't quit making these videos.
Best regards,
Just wanted to thank you for this. I decided to try building a computer in Minecraft so I can better understand how they work, so this video series is a godsend. I already got the 555 timer working (though for the actual I'll use a hopper clock) so it was good to understand how they work.
thats genius, with the 3 super real examples
Wonderfully described videos! Clear precise instructions! If I was still working in education, I’d be showing your videos to students.
I am computer illiterate apart from web surfing. But. I enjoy these videos because Ben has a nice voice and I certainly *do* LOVE electronics!
Thank you Ben for your precious work! I have just finished to study all your 44 video ! Everything is perfect made . I didn’t know anything about Fetch or Register or whatever and now I can understand the elementary way a computer works. Thank you! I bought the package to build it , I can’t wait to receive it! 🙏🏻👍🏻
You are so good at explaining - it is a joy to watch
Whether this makes money or not for the publisher. This information is highly valued to viewers
I have yet to view your 555 as timer videos. But I wanted to congratulate you on thinking to post these types of videos for people who seek to learn this stuff. I’ve built the examples and I’ve made use of the crystals just as they’re demonstrated, just as I’ve used my real time clock with the CR2032 button cell battery. I get a strong sensation from seeing the video, that you prefer (or maybe have had more experience with) TTL driven clocks. It now occurs to me that chasing the TTL clock (I guess I’m locked in phase) is the real key to understanding these signal styles that you have so cleanly demonstrated. This is some very important wisdom. It’s the true meat and potatoes for making the decisions regarding circuit design. Also, I can use this to more fully understand hardware design languages like verilog or pshvhdl. Thank you so much your videos have made my 2019 a ‘yippee’ year so far!
I have just discovered this set of wonderfully explained videos. Thank you very much for your time and effort.
Best eletctronics channel out there. Period.
01:20 Another idea is to solder it to a DIL socket.
02:18 There's another problem with such a switch: we cannot control the exact moment at which we will switch to the automatically clocked signal. This may be a problem sometimes. So a better idea would be a _single_ clock which can be _advanced_ either manually or automatically depending on the switch's position, so that it would always start an entire new cycle from scratch after switching to the automatic mode, and finalizing the last pulse after switching to the manual mode, but just holding up the next pulse until manually triggering it as a one-shot. That's one of the reasons I was wondering about how to reuse a _single_ 555 chip for this dual purpose.
Could you provide schematics for bistable switched mode using single 555?
+Nerijus Vilčinskas
Here's what I went with:
circuitdigest.com/electronic-circuits/555-timer-bistable-multivibrator-circuit-diagram
If you start from the astable multivibrator circuit from the first video, I think it should be possible to add some extra components to be able toggle it between astable and monostable mode.
Maybe something like:
* A switch to switch the lower trigger input between the capacitor voltage and 5 V - when it's at 5 V, the 555 won't notice that the capacitor voltage is low so it will be stable in the low state.
* A button to pull that some lower trigger input high when the switch is in the position for the monostable mode. That should be enough to start one cycle.
This scheme should give a bit of debouncing, because it's just manipulating the trigger input, which in turn causes the SR latch to change state. But if you press the button long enough that the high trigger input triggers to reset the latch, I'm not sure what happens. Maybe the button should ground the high trigger input too.
If you can make it so that the extra controls only deactivate the triggers (either the lower or the upper depending on if the button is released or pressed) then you should only be able to slow the cycle down compared to the astable case, which I think is good. And it's if enough if a trigger activates once, so there's your debounce.
Thank you so much for making this video series it has increased my understanding of electronics immensely.
Just watched about 2 hrs of your videos in a row and realized I hadn't :thumbsup: any of them, shame on me. So I decided you deserve another subscriber, sub'd. Thank you for you invaluable educational demonstrations. You sir are an extremely good teacher, you deserve every sub you get!
Congratulations on 555k subscribers!
I want to pay all my college tuition fee to Ben !
Dude, I bought this kit from Ben last year. I think I'll build it today. Yay!
The way you explain things is incredible !
I like the colored-ball end sewing pins for test points.
I remember seeing somewhere that 555 timer is the number one most sold chip, which is the most successful chip in semiconductor history!
Great stuff, love the finished product of the clock module here!
I get more insides into 555 operation that in 3 years of engineering classes
Enjoyed this one as well. Thank you.
Cant you use a capacitor to debounce
Yes
This I believe is on purpose to demonstrate astable, monostable and bistable modes of 555
555/556 is the "Swiss Army Knife" of the electronics world.
"break before make" - so they break before you can make something with them?
Levin Street LP “break contact on one side before make contact on the other side of the switch”
@ku hes talking about facts, dont woosh him
Darn, i was hoping you'd use 2 555s not 3, i have a 556 in my parts bin i've been meaning to use...
Maybe half the 556 for the astable, the other half for the bi-stable, and a flip-flop for the mono-stable?
Remove the limiting resistor to the variable R, and add the stepper button in series. That way the “switch” is nothing more than stoping the pulse, and while it’s not pulsing, the push button sends another pulse.
Does voltage between the two modes matter? For instance, my async has an output of 1.7V, while my manual has 2.6V.
Shouldn’t there be an OR gate between the /reset’s NOT and the thresholds comparator output? Otherwise there could be contention issues in the SR’s R input and current could be sinked to either the comparator or NOT’s outputs (which could presumably damage them)?
Is there any particular reason why one should use the reset pin instead of the comparator pin to reset the latch?
In order to reset with Pin 6, you'd need to connect that pin to a voltage above 3.33 V, so probably 5 V. In order to set with Pin 2, you connect it to a voltage below 1.67 V, so probably Ground. But we want to dpdt switch to toggle between set and reset. So Pin 4 is convenient, because you reset with that pin by connecting to Ground. So the switch just toggles whichever pin is connected to Ground.
Amazing videos so far Ben! I'm just having a little trouble with the switch. The LED starts off and when I toggle the switch it turns on, however it doesn't turn off again when I toggle it again. I can fix the issue by unplugging pin 6 on the 555 rather than having it set to ground. FYI setting it to 5v stops it working altogether.
Basically I'm wondering if anyone knows why this is and more importantly if I leave 6 on the 555 unplugged will the circuit still work as intended?
Amazing explanation!
If using 555 as SR Latch we could use colored LEDs. Green - S, RED -R. It seams nicely...Greetings.
John From Serbia
Hi Ben.
Thank you for an amazing project!
Now I am on my way of building it.
I have difficulties in programming the microcontroller.
Is there any way to contact you and ask the questions?
Thank you.
Regards
5:30 Can't the switch bounce "all the way back" ? Meaning it might reach S then bounce back to trigger R and back again to S ? In which case the SR latch would provide nothing much.
Furrane no. If you imagine a piece of metal hitting the floor, it will ‘bounce’ a few times before coming to a stop against the floor. This what is happening inside the switch. Now imagine the metal is upright on the door saddle between the hall and the kitchen. Let it fall towards the kitchen and it will bounce a little as it hits the kitchen floor but it won’t bounce enough to double back and bounce on the hall floor.
Maybe for a few presses as it’s failing, but normally I don’t think so.
I think the debouncer, in this case, is useful in very few cases. (in the previous video, it was 100% useful! even though it is random)
E.g if you debug and as you said you wait to switch into manual mode when you change to manual, the signal will be 0 on the manual clock (because you don't press it). So from there won't come any extra 1 signals.
It could only happen, when you change back from manual to clock and the clock when you change is in 1. Then some quick behaviour could happen, but not at debugging. So that would be less fustrating, I guess :D
Hm, I was unsure about this too, but after some more thinking, I believe that Ben's point stands. Imagine you have a high clock as you switch to step mode. As you slide the switch, just at the boundary of disconnecting the astable timer, contact could be intermittent, thereby potentially causing unwanted clock pulses.
Hello Ben Eater! I was wondering if I may use this circuit for IEEE members at Purdue University Northwest for educational purposes. This covers a lot of important concepts for Electrical Engineers and I’d like to show new students how electronics really work!
Hello. I've noticed that you replaced the electrolytic capacitor with a ceramic disc capacitor. Is it okay to interchanged the two type of capacitors in your usage of them and they will still performe that same function no matter if you interchanged them, or is there a particular reason why you would use an electrolytic capacitor instead of a ceramic disc capacitor or vice versa? There are a couple of different ttype of capacitors such as electrolytic, ceramic disc, tantalum, mylar, etc. out there and I'm wondering if it's okay to use them interchangeably or is it that these capacitors are each use for different applications?
They are interchangeable! Some are just a little bit cheaper.
Reviewing this while looking at what I built and I don't have it set up like this at all, even though it works. I have pin 2 going to a 1k resistor to ground (pull down resistor?) and then if the switch is on, then ground is directly connected to pin 2. And yet it works when I flip the switch. Pin 4 has a pull up resistor and connects to the other side of the switch, so that looks right. So I moved the pull "down" resistor to where it should be as a pull up resistor and it still works. It's like pin 2 pulls itself up automatically from the chip. Weird.
Where did you get the double pole toggle push button switch, having trouble finding one like that?
Is there anyway to do this kind of thing with Dip Switches instead of just a push button? Curious is there's a way to do this without any soldering, lol
There is a way to do it. It depends on which DIP switch you are using.
Can someone explain to me how the switch @ around 4:09 where he's showing how the switch normally works? I don't understand how the LEDs turn on there. Thanks!
See, the switch that Ben is using is a 'double throw switch', which has a 'fixed' contact pin(Physically speaking, the pin in the middle of the switch) and a 'variable' contact pin. The fixed contact pin is connected to the 5 V power supply. The 'variable' contact pin switches between 2 connections which in this case, are the 2 LEDs with current limiting resistors connected in series with it. So, when we press the switch, it 'switches' between the 2 LEDs, lighting them up when the respective pin is in contact with the respective LED. I hope you have understood this.
here's a noob question. What's the point of all the resistors on the connections? Why not simply have a direct connection?
The resistors are there to keep the 5V pulses from damaging the LEDs, which usually operate at around ~3V or so
Ah okay thanks
Elmer Gomez the ones not on the LEDs are to limit current. 5v through 1k is 5mA which won't burn out, for example, transistors in the ICs.
Actually both can damage the LED. Too much voltage will blow the wire attached to the PN silicon, and too much current will melt the wire (inside of the LED). We are playing with power. So your Resistor in series with the LED = ( [(Voltage Source) - (Voltage drop across the LED, or another way of saying it LED Voltage)] / LED current. www.resistorguide.com/pictures/resistors-in-LED-circuits.png
See >>> www.resistorguide.com/resistor-for-led/
You can't have too much voltage without too much current for a forward biased diode!! Reverse bias yes you can have too much voltage and cause avalanche failure.
where do you get the Double-pole toggle switch?
There are a lot of on line suppliers: Digikey, Newark, etc
The included switch i have received is not working the same way..
Someone else wrote this fix for that:
To anyone that has bought Ben's timer kit: the switch provided there is a make-before-break switch, as opposed to a break-before-make! However, there is an easy solution to fix this.
Simply invert the logic that the gate in the video uses; i.e.:
- Connect the switch's central pin to 5V, not ground
- Use pulldown resistors to GND for pins 2
and 4
The rest of the circuit is identical. By inverting the logic, you are essentially converting the make-before-break switch into a break-before-make switch.
Nice diagrams.
I understand that you wanted to present all those 3 practical use, but I think you could have used just 2 555 times by connecting the sides of the toggle switch to the clock and the naked button, with its base connected to the de-bouncing 555.
Wouldn't that also debounce your astable 555 clock? Which would cause it to miss pulses when going too fast.
Can someone help me please? I connected the circuit in the exact same way as he did but it doesn’t work. When I plug the power in the light is off, but when I press the switch the light comes back on. The problem is that when the light comes back on the switch won’t turn it off again. I’ve tried rebuilding the circuit, pressing the switch multiple times, and using a different switch. Nothing has worked so far. If you have any solutions to this I would appreciate it very much! I'm stuck!
Thanks for the reply. I will try this later on. I have ordered 3 sets of damn switches from america haha! Hopefully what you said will fix it. Thanks again!
@Zepu Li I need to figure out why setting it to high fixes this for me as well...
Hey man, did you ever fix this issue? I have the same problem. Thanks in advance!
You're a true legend
Does the current supplied by the 5v power supply matter at all?
Can i use a 3.3KOhm as a pull-up resistor instead of the 1K ones you used? This way i think i could reduce the current draw, if it doesn't mess with 555's internal circuitry.
It shall not mess but im new in this topic
Just try it out
@@aqbaplaygames3435 Well... then i'm going to try it on a separate circuit first, so that i don't explode my entire work.
My bistable always has the light on... Please help!
Describe the problem
@@EvanSamano no problem
How do you know exactly what length to cut your wires?
Holobrine They are all precut and kept off screen for the examples. He has previously sized the wires and shaped them then removed them from the circuit.
can we just debounce the push-button like this too?
Ben, does it matter what type of capacitors you use in a RC circuit? I remember using a lot of electrolytic capacitors for things I built. I remember having a hard time finding the values I needed in any other form. You can tell I use to do a lot of shopping at Radio Shack.
Both 1&2 nice TKQ
can someone help me, im trying to find that Double-pole toggle switch but I cant find one in the UK that is breadboard compatible can any one help?
Minefan48 sorry man, I've tried and failed to find a decent one. If I were you I'd just solder some single core wire to each pin on any toggle switch. That's what I've done and it's worked out well so far.
Jordan Hall I found some on Amazon!
You found breadboard compatible toggle switches? Can I get a link?
Jordan Hall I'll have to find it so you have to bear me
I think the Double-pole toggle switch he is using is the TL2230EEF140 from E-Switch (the EE stands for latching OA would be momentary)
It can be found on mouser.com for example if you don't find any in amazon or your local electronics shop
I've seen someone debounce a switch just by putting a cap across the contacts. Is there a reason why the approach using a 555 is better?
Hi Mr: Ben ,my name is TONNY from Africa I really appreciate your work and I have been watching your videos and they have taught me alot, today I want to you to help me in my project:
In this project I have a (HUCULESE INSTICT P8 DJ controller)made in China, This controller works very fine but their is a problem with its
CROSSFADER ) The C-fader was made of carbon,and with time when scratching , the carbon gets off quickly then you have to replace it with another new C-fader for every 5months which is very annoying,and as in Africa getting a spare parts sometimes you have to make an order which is very expensive,Now here is where I need your help I bought an Arduino starter kit because of your interesting work,but I still have alot to learn,Now Mr Ben .I want to reprogram this DJ controller such that it can use an optical C-fader system ,I have all the materials for this project but I don't know where to start from like the software for reprogramming the DJ CONTROLLER .So to put it in short I want to remove the (carbon potentialmeter
and replace it with optical potentialmeter)how can I get this controller's IDE software like arduino uno and others uses arduino ide plus where do I start from eg : changing the potentialmeter codes to whatever I prefer,
If u really want to blow ur mind check out the 556 timer! It's like taking a 555 up to 11. It's one number better innit?!
Can someone help me please? I connected the circuit in the exact same way as he did but it doesn’t work. When I plug the power in the light is off, but when I press the switch the light comes back on. The problem is that when the light comes back on the switch won’t turn it off again. I’ve tried rebuilding the circuit, pressing the switch multiple times, and using a different switch. Nothing has worked so far, I think it may be the switch is only single pole. But that wouldn’t make sense because it has three connections that makes it appear as a double pole switch. If anyone can help me it would be appreciated!!
Im having the exact same problem! Did you find a fix?
Hey, I know it has been a year, but I have the EXACT SAME problem as you! Did you ever find a solution?
555's are the WD40 of the electronics world.
Great video's learnt allot, thanks man!
Hm , the Discharge output is an open collector output of /Q output, giving Q.
@ 8:24 where you start explaining the breadboard, we see a resistor of also 1k connected to RESET pin, which does not exist in scheme previously, nor RESET appears to be connected to Vcc. Please, correct me. Thank you!
Why can not we simply use a tiny capacitor between pins of button to achieve de-bouncing problem ?
Ömür Ölmez you'll build up a charge across the capacitor that must go somewhere when the switch is open/closed.
Ben what dpdt push buttons are those.
My Bistable Clock just won't work! I've checked the circuit like a million times. Can Someone please help?
And is there a replacement for the Bistable Clock?
@3:55 “a property of these switches, which is...” Nice wordplay dropped into a technical video.
👨💻UA-cam 👍Teaching & making Scientist and techy Engineers & Awareness + without a degree -
I'm trying to recreate this computer in Minecraft with 0-tick repeaters, so far everything is identical. Wish me luck!
Wait, so I wanted to order your video parts to build the computer myself. Since I live in Belgium, I wanted to source the parts from here. When looking at your part list, I got stuck on the SPST switch. After almost 2 hours I figured out you are using a dpdt switch. Is this item on the partlist incorrect? I know you are only using one side at a time. Is this why you recomend a spst switch? Great vids btw. Feel like I am learning more than in school.
To understand clearly the difference between astable, monostable and bistable:
www.555-timer-circuits.com/operating-modes.html
A good idea would be to brush up on your basic electronic theory such as f2f time constants
You can use 555ne ic
Eng Riad Almadani yes
For anyone else following along, the previous video failed to mention tying pin 4 high on the 2nd 555 timer, which seems to be added here.
I took apart this weird bug repeller and it had a 555 timer in it
your parts list doesnt mention those push switches 😭
It does he mentions an spst switch but in his vids he saids dpdt switch I asked above if this is a mistake or a recommendation, since we are only using one side.
where do you pull those resistor values from? why do you use a 1kOhm resistor to pull up pin 2 on the T555? why not 1MOhm? After all you're shorting it to ground for extended periods. Why not 100MOhm? Why not +InfOhm? What are the advantages and disadvantages of different pull up resistor values and how do you decide which one to use? Or do you just pull those values out of your rear end?
Where can I buy all these chips?
the internet
:P
For the resistors, LEDs, and such, check DigiKey as their parts are really cheap. ICs and breadboards are more expensive on DigiKey so try finding an electronics surplus store - generally fairly decent prices, and more willing to give you deals if you're buying a lot. I found the ICs needed for the whole project at 1/2 the price they would've been on DigiKey (and without shipping). Also satisfies the "but I want them now" itch, and they can be super fun to browse.
02:25 Example of a switch bounce @ 05:55 ua-cam.com/video/HyznrdDSSGM/v-deo.html
Ahhh. Yes. The 555 latch.
why not use a 556 timer? you would get the same effect
Why not buy an arduino? You would have all the functions of the 8-bit computer.
@@jacobtohahn That is what I was trying to say by ironically exaggerating Mateos question about the 556.
The whole point of this thing is building it. Of course you could swap the circuit with a 556 but that would kind of be the same as just swapping the whole thing for something pre-build.
@SecondASMR but this isn't reddit
i have been looking into the 556 (dual timer) or the 558 (quad timer) to make this clock circuit . it is the same theory and concept just less chips and less space used on the breadboard , with a 558 there is one 1 power pins and 1 ground pins instead of 3 power pins and 3 ground pins (one for each chip) with the 555 timers. i don't have any 558 timers so i am working on making it with a one 555 and one 556. my questions are : is there any down side of using a 556 or a 558 instead of all 555's? are 555's more (or less) reliable than the others? is it likely for each timer to interfere with the others? etc?
Sure, but A and B is a fucking lot to work with.
Why would you want to use an entire 555 timer if you could have just used an sr latch?
I guess the idea was to complete the overview of the 555, studying the 3 modes.
You did not explain the break before make concept
Break Before Make is similar: For example, if we want to move to another spot, you have to break the spot first before moving to another one.
NOOOOOOOOOO i ran out of 555, i gotta order more
why not using 556 timers?
in the description should be "2x 555 timer" instead of 1x, right ?
i think those parts are the parts he added to the circuit in this video, not all the parts on the breadboard.
if you opend up your eyes it clearly says he listed the parts from this video
Solder has a letter l in it
Wouldn't it be better to just bring 2 wires from the clock and the button, and just switching between them, instead of putting another triple 5?
I'm sure you could optimize the circuit further by reusing the 2nd 555 timer. With a bit more optimization, you could probably even get away with using a single 555 timer since we don't really need both states to be running at the same time.
I just burned my 555 timer and finger 😢😓
Ben, please work with ben Heck