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jean bender
Joined: Feb 21, 2010 Posts: 139 Location: france
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Posted: Mon Nov 21, 2011 2:28 pm Post subject:
problem with cd4017 Subject description: sometimes, it's too much for me... |
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Well...
I've built a first 8 step sequencer based on Ken Stone's gate sequencer. I used a 555 clock taken from casperelectronics ( forget the right part of the schematic !!):
Well, it was a cool build, everything worked once it's been finished.
Today, i wanted to build one more sequencer, almost the same thing. I used cd4017be ics.
Nothing worked. To test my chips, i've put the one i use today in my first sequencer : it was working.
I really don't understand why my "built from the day" doesn't work. I only can get two steps, the other ones don't work.... Really weird.
Would somebody have an idea ? I wonder if the led i use are ok for this kind of design.. But, is there any "bad" led for lunetta ???
I've tried to breadboard several other designs with cd4017, but i've always got only two steps...
thanks for any answer/ help/ idea...
_________________ http://h.a.k.free.fr/
www.electroncanon.org |
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Cynosure
Site Admin
Joined: Dec 11, 2010 Posts: 966 Location: Toronto, Ontario - Canada
Audio files: 82
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Posted: Mon Nov 21, 2011 6:13 pm Post subject:
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Does it reset after two steps or does it just pause for a bit and then goes back to the first step?
What do you have connected to the reset pin of the 4017? You show the schematic for the oscillator but not the 4017 portion. What schematic are you following for that part? |
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jean bender
Joined: Feb 21, 2010 Posts: 139 Location: france
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Posted: Tue Nov 22, 2011 12:07 am Post subject:
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Here's the basic schematic of my sequencer :
It's a bit weird, sometimes it resets, sometimes it pauses and go back to one step... _________________ http://h.a.k.free.fr/
www.electroncanon.org |
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cheese_nucleus
Joined: Dec 22, 2009 Posts: 24 Location: germany
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Posted: Tue Nov 22, 2011 5:33 am Post subject:
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hey! i also hab some weird problems with 4017 ICs. in my case it had to to with the 100K pulldown resistor on the reset pin (15). i would try to disconnect the whole reset circuit and pull down pin 15 through a wire.
as you described your problem, it might also be a bad chip, when your circuitry works fine with another 4017.
with LEDs, there shouldn't be any problems, if they're powered by the transistor. |
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Cynosure
Site Admin
Joined: Dec 11, 2010 Posts: 966 Location: Toronto, Ontario - Canada
Audio files: 82
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Posted: Tue Nov 22, 2011 7:47 am Post subject:
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I used 10k on for the resistor to ground on the reset pin. Try without the reset option like cheese_nucleus suggested. If that fixes it, then try lowering the resistor value until it works like it should. |
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jean bender
Joined: Feb 21, 2010 Posts: 139 Location: france
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Posted: Tue Nov 22, 2011 7:53 am Post subject:
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Hi !
I've built it again this morning... It worked. No way, i don't really understand how it goes, sometimes.
I've tried with and without pulldown resistors, both ways work.
I used the same components as yesterday, the same breadboard....
very weird.... Sometimes, cmos chips seem to live by themselves...
thanks for your help, next time, i'll use your tips if i've got troubles !
see you soon ! _________________ http://h.a.k.free.fr/
www.electroncanon.org |
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Kabzoer
Joined: Feb 07, 2011 Posts: 82 Location: Belgium
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Posted: Tue Nov 22, 2011 11:07 am Post subject:
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I've got the same problem, you can fix it by lowering the pulldown resistors on INH, RESET, and CLOCK, from 100k to like 10k or 20k, this solves it with my chips... _________________ http://soundcloud.com/contraspect |
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JingleJoe
Joined: Nov 10, 2011 Posts: 878 Location: Lancashire, England
Audio files: 14
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Posted: Wed Nov 23, 2011 3:10 am Post subject:
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deadbeat wrote: |
very weird.... Sometimes, cmos chips seem to live by themselves...
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I once heard life defined as: Anything that uses the energy around it to reduce entropy.
This CMOS chip uses electrical energy to create a very orderly sequency of lights/sounds ... and is therefore, alive? |
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Kabzoer
Joined: Feb 07, 2011 Posts: 82 Location: Belgium
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Posted: Wed Nov 23, 2011 9:07 am Post subject:
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JingleJoe wrote: |
This CMOS chip uses electrical energy to create a very orderly sequency of lights/sounds ... and is therefore, alive? |
And you expect me to be able to sleep for the next few weeks? _________________ http://soundcloud.com/contraspect |
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JingleJoe
Joined: Nov 10, 2011 Posts: 878 Location: Lancashire, England
Audio files: 14
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Posted: Thu Nov 24, 2011 9:31 am Post subject:
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Kabzoer wrote: | JingleJoe wrote: |
This CMOS chip uses electrical energy to create a very orderly sequency of lights/sounds ... and is therefore, alive? |
And you expect me to be able to sleep for the next few weeks? |
No
"Thinking alot is scary"
~ H.P. Lovecraft. |
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