555 timer newbie question - Page 1
Forum section: electronics / beginners

author: Shadetreeprops
author_rank: Regular Contributor
timestamp: February 24, 2016, 11:42:27 pm
content: Okay, so first off, i have no real knowlege of the 555, with that said, i have never used one.But i have a project idea using a Nixi tube.Can i use the 555, where when i press a button it counts down 9-0, by pressing a button, but stops at 0, until i reset the circuit on it, sending it back to 9, then pressing the button to bring it down again?I have been reading Electronics all in one for dummies but im starting out, i have jumped to the section on the 555 but i am still not sure if it can do what i am asking. I really do not want to over complicate this. By having to use a shift IC, and arduino bleh bleh...casue i have tried my hand at programming. I found one thing about it. I DO NOT LIKE PROGRAMMING.It is for a novelty prop i am going to build, and thanks for any help.

author: retrolefty
author_rank: Super Contributor
timestamp: February 25, 2016, 01:42:57 am
content: The 555 cannot 'count' but rather is a clock generator. Would take extra digital chips to do what you want. Today the best solution for your needs is a 8 bit micro-controller, but you don't like programming.

author: Shadetreeprops
author_rank: Regular Contributor
timestamp: February 25, 2016, 02:06:22 am
content: Quote from: retrolefty on February 25, 2016, 01:42:57 amwell that is not what i needed LOL, but i see what you mean, while wating for a answer i kept trying to understand the 555. Its sort of a on off, ticker in lamen terms. but maybe some kind of analog mechanical solution. a rotational micro drum that moves the connection as needed. on a spring mechanic, that wont reset until an action is taken..like a revolver.

author: Skimask
author_rank: Super Contributor
timestamp: February 25, 2016, 02:12:19 am
content: 555 timer plus a 4017.Microcontroller...best solution...bah...

author: mstoer
author_rank: Contributor
timestamp: February 25, 2016, 02:16:28 am
content: Quote from: Shadetreeprops on February 24, 2016, 11:42:27 pmYou want a binary up/down counter IC and you feed it the 555 output (to count seconds or whatever timing you want). They usually have a reset pin.

author: retrolefty
author_rank: Super Contributor
timestamp: February 25, 2016, 02:16:34 am
content: Quote from: Shadetreeprops on February 25, 2016, 02:06:22 amLOL, I don't especially like programming either as soldering is my favorite programming language, but it will be a whole lot easier and faster to master basic C programming and getting a $2 Arduino Nano clone to perform your task then any mechanical solution.

author: Paul Moir
author_rank: Frequent Contributor
timestamp: February 25, 2016, 02:55:13 am
content: Personally I'd go with a 555 clicking away driving a 74193 driving a 74141. Google tells me you can stop a 555 by pulling RESET low so a NC switch and pullup would do there. The 74193 has a borrow output that goes low when you hit zero so that could be your other stop. To reset hit the PL line, and have the preload being 9.The '193 outputs binary so that's what the 74141 BCD to nixie driver is for.(My main reason for going this way is the 74141 saves some work. But you will need a 5v supply... Otherwise 4017 but you'll need some drivers on it's outputs.)

author: vk6zgo
author_rank: Super Contributor
timestamp: February 25, 2016, 03:14:07 am
content: Quote from: Skimask on February 25, 2016, 02:12:19 amI agree,as a decimal counter,a 4017 is the obvious choice.

author: Shadetreeprops
author_rank: Regular Contributor
timestamp: February 25, 2016, 06:28:46 am
content: Wow, all these are great answer, except the one concerning programming...i rather eat hot solder.but the one that seems up my skill level is the one that is the 555 with the binary up down counter set up.Its going to be for a steam punk prop gun, i have several vacuum tubes that have the nice after glow, and tie that into a nixie to fake count the ammo, and use a clip drop and reload function to reset the circuit back to 9. pull trigger count down 0, drop clip reload, reset..wash rinse repeat.im working on 3 projects at one time ATM. one is a new variable 12v hack job power supply, 1 xbox PSU, 2 1Meg pots from Atari paddles, 1 cheap Harbor Freight Multimeter to act as volt meter. and some old scope attachments hacked together to make multi probes out for diffrent power hook ups.one pot will be used to vary volts. and the other to set the voltage going to the hacked in multimeter to not over power it and burn it out. then just cut the probes wire in to line to read the volts coming out as i adjust the other pot..then for GIGGLES AND LAUGHS gonna ram it all into a 50oz coffee creamer container, and put all the dials on the lid. with the atari control coming out of it. and little bolt legs..to say LOOK I MADE THIS OUTTA JUNK HACKED BOGGED and HOT SNOTED IT INTO MY Garbage PSU.

author: Aodhan145
author_rank: Frequent Contributor
timestamp: February 25, 2016, 05:22:08 pm
content: I understand the thing with programming. I also think it is more fun to use logic chips but micro controllers are too handy in too many situations. You should just bite the bullet and learn how to code. If you have the right mindset for electronics coding shouldn't be that much more difficult especially with arduinos. Since you are going the logic route, try a 4026 counter it has seven segment output..

author: Skimask
author_rank: Super Contributor
timestamp: February 25, 2016, 08:08:42 pm
content: A 555 timer, or push button switch to get your 'trigger' pulsesAnother push button for the reload functionA 4017 decade counter10 LEDs (or not, whatever you want to do) and current limit resistors (330 ohm, whatever works for whatever LEDs you use, if you use any)A 4013 D-type flip flop with set/reset inputsAn "AND" gate (7408 is a quad AND gate)The bottom push button in the picture is the "reload" buttonThe top one is for the triggerPower up, 'full ammo'Click the trigger 10 times, won't 'click' any more until it's 'reloaded'.

author: Audioguru
author_rank: Super Contributor
timestamp: February 25, 2016, 08:29:12 pm
content: I think since you are using old fashioned Nixie tubes you should make the entire circuit using old fashioned vacuum tubes.

author: Shadetreeprops
author_rank: Regular Contributor
timestamp: February 26, 2016, 02:43:21 pm
content: Quote from: Audioguru on February 25, 2016, 08:29:12 pmI got vacumme tubes a plenty..but they are so far out of my league, that all i know how to do witht hem is make the heater light up...for the glow...outside that i have no clue how they are wired.i have only been at this EE stuff for a bout 2 months..and you guys and gals have years on me. I have never been given so much help on a fourm before. it makes me happy to to think that maybe this is my knack..casue anything else that stumps me peeps on the forums chastised me for not knowing.AND I REALLY LIKE THE IDEAD OF MAKING FUNCTIONAL ART....pluse EE do not see caps as yelling. its how they write to clearly understand what a schem says.

author: Philfreeze
author_rank: Regular Contributor
timestamp: February 26, 2016, 02:55:31 pm
content: Quote from: Shadetreeprops on February 26, 2016, 02:43:21 pmWe are on the internet. If you write something in all caps I assume you are screaming and I read it that way. That is just how the internet works. If you want to mark something in your text then please use the provided html tags likeUnderlined,ItalicorBoldCode:<TEXT> for underlined<TEXT> for italic<TEXT> for boldHow I would do it:Get a bidrectional counter (or build one with JK-FF).Connect the output of the 555 to the clock input of the counter.Use an AND-Gate (discrete or in chip form, whatever floats your boat) to catch the '9' state and connect the inverting output of the AND-Gate to the Reset Pin.And now you just use a switch or a button to reset the counter.How it works:The 555 will output a clkThe clk increments the counterWhen the counter reaches the '9' state the inverting AND-output will be pulled low.This will pull the Reset pin of the 555 low.The 555 stops producing the clk because it is held in it reset state.When you push the button the counter will be reset to '0' and the inverting AND-output will go back to a logic 1.The Reset pin of the 555 will be pulled high (released) and it will start producing the clk again.

author: Skimask
author_rank: Super Contributor
timestamp: February 26, 2016, 03:31:52 pm
content: No need to PM.The parts list is in the post. And it's already dumbed-down about as far as it can go. 3 cheap chips, a couple push buttons, some LEDs and resistors, and a 9v battery, and something to mount everything on or solder to, and done.I'll "help", but I'm not going to build it for you.Google the part numbers for datasheets, match up the symbols in the picture to the datasheets, wire up as such.The 4017 is a 'decade counter', eg. counts in groups of 10's. Starts at one end, gets a pulse, works its way to the other end.The 4013 is a 'latch', basically keeps track what's going on...either shooting, or reloading.The 7408 AND gate is there to let the trigger pulses thru.Power up the box and the decade counter is set to zero, the AND gate won't let trigger pulses thru, the latch is set to reload.Click reload, the latch 'remembers' you hit reload, the counter is reset, and the AND gate lets trigger pulses thru.Click the 'trigger', the decade counter counts up by one.When it gets to the end, the last LED sends a pulse to the latch which resets it, shuts off the AND gate, which will no longer let trigger pulses thru, and since the counter is at the end, all it can do is go back to the start. The trigger pulses won't do anything because the AND gate won't let them thru. Have to go back to the "Click reload" step above.Stand by one...

author: Philfreeze
author_rank: Regular Contributor
timestamp: February 26, 2016, 03:39:56 pm
content: Quote from: Skimask on February 26, 2016, 03:31:52 pmdoes he want a decade counter?If he does want one you could use my idea and replace the AND gate with an inverter (or just a normal transistor with a resistor).

author: Skimask
author_rank: Super Contributor
timestamp: February 26, 2016, 03:43:11 pm
content: Save the attached file to your computer. (it's the circuit file you'll need in a minute)Go to:www.falstad.com/circuit/circuitjs.htmlHit "FILE", "Import from local file"Select the "ammocan.txt" file and it should load up on your PC and should be the same thing you see in the picture posted earlier.Click on the upper push button for the trigger.Click on the lower push button for the reload.Don't click on them too fast or a pop-up will come up asking you to change things. Just ESCape out of it or click cancel or whatever.

author: Skimask
author_rank: Super Contributor
timestamp: February 26, 2016, 03:44:22 pm
content: Quote from: Philfreeze on February 26, 2016, 03:39:56 pmFirst post says count down 9 to 0, so I'm assuming 10 counts is good enough and/or what he wants.Like a lot of other things, a lot of vague information going around.

author: Philfreeze
author_rank: Regular Contributor
timestamp: February 26, 2016, 04:20:20 pm
content: Quote from: Skimask on February 26, 2016, 03:44:22 pmOh, I din't realize that he wants to count down. Turns out I miss interpreted the funcionality anyway. I thought it was supposed to count down by itself after pressing the button.Your solutions fits it though and it is probably the simplest one.

author: Skimask
author_rank: Super Contributor
timestamp: February 26, 2016, 06:59:57 pm
content: I can't think of anything simpler. I'm sure there's a counter chip out there with discrete inputs to do what the D-FF and gate does, but I can't think of what they are. All the ones I've seen/used roll over at the end of the count. None of them 'stop' at zero waiting for a reset.Normally, I'd do something like this on a 14 pin PIC or similar, like maybe a 16F527. One chip, 2 buttons, a 10 segment bargraph display, not even use current limit resistors, and use wires on the pins instead of push buttons.

author: Shadetreeprops
author_rank: Regular Contributor
timestamp: February 26, 2016, 10:14:10 pm
content: Quote from: Skimask on February 26, 2016, 03:31:52 pmI will take the help as i work on this thing. But no sir, i do not want anyone to build it for me. That is the fun of it..to see what you worked on come to light. Literally.So its not so vague.i want to make a gun. a prop gunthe nixi acts as the ammo count down. starting at 9 rounds.when you hit the trigger of the gun, it goes down to 0, at zero, it will not just reset. untilI pull the props clip out, and put it back in, acting as if i am reloading the gun with a fresh clip of 9 rounds. Then it will go back to 9.Another project i am working on is a phaser gun...propbut i have already mapped the circuit, and all that so once i get it made i will share it with you guys..and let you see what i did..and my thrid project is just a functional lamp.that has those meters i posted in general that i found. they will tick on a nd off, when the Power Cell is active...prop....and it will be a FALLOUT 4, radioactive cell charger..for the lazer rifles...and then i will make the rifle, so the cell can be put into it as well. so a functional lamp, and prop part for the gun when i build that.I already did one non function ODE TO STAR WARS GUN.that is basically done on my channel shadetree props.here is one of the images for it. at the 70% stage i had to hand make the handel.

author: Skimask
author_rank: Super Contributor
timestamp: February 27, 2016, 12:14:38 am
content: Fair enough.Then get the parts mentioned above together, build up the circuit with LEDs to make sure it works the way you want it to, then move it over to the nixie tubes.