broke my own circuit - 4017 decade/Johnson counter

DewDude

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Oct 26, 2011, 10:46:16 AM10/26/11

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so im building a simple light chaser circuit out of a 4017 counter and
555 timer. the 555 timer circuit works. my problem is with thr 4017.

according to several schematics ive seen...and behavior in electronics
workbench/multisim, connecting the reset to output q4 causes the chip
to reset when q4 fires.

real-life behavior i different. if reset is connected to anything
except just ground, all it'll do is blink the first led.

any suggestions?

Ian Field

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Oct 26, 2011, 3:39:05 PM10/26/11

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"DewDude" <dew...@gmail.com> wrote in message
news:da4cb5a9-8d74-4143...@q35g2000prh.googlegroups.com...

You're resetting from the wrong end of the counter.

DewDude

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Oct 26, 2011, 4:12:54 PM10/26/11

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On Oct 26, 3:39 pm, "Ian Field" <gangprobing.al...@ntlworld.com>
wrote:
> "DewDude" <dewd...@gmail.com> wrote in message

i dont see how. the counter will start with output q0....it
automatically cycles back to q0 after firing q9, the reset is supposed
to allow me to recycle back to q0 after firing a specific number of
leds.

explain your reasoning or stfu.

Ian Field

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Oct 26, 2011, 4:36:55 PM10/26/11

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"DewDude" <dew...@gmail.com> wrote in message

news:dc3cca40-a86f-4a86...@d33g2000prb.googlegroups.com...

vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv

I had another suggestion but since you're an offensive little cunt I won't
bother.

Jamie

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Oct 26, 2011, 7:39:58 PM10/26/11

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I just looked at the PDF on that chip. It looks to me that you need to
directly connect the Q4 output, if that is the one you want to use?
directly to MR input.

If you have a scope, make sure you are making your minimum levels.
Also, you may want to put a rail cap at Vdd. Make sure your supply
rails are steady.

Jamie

Jamie

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Oct 26, 2011, 7:41:49 PM10/26/11

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Ah LEDS, I bet you are loading down the line! :)

Insufficient levels.

Jamie

Jeffrey Angus

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Oct 26, 2011, 7:38:04 PM10/26/11

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On 10/26/2011 3:36 PM, Ian Field wrote:
> I had another suggestion but since you're an offensive little
> cunt I won't bother.

Spot on sir. Too funny.

Jeff-1.0

--
"Everything from Crackers to Coffins"

Michael A. Terrell

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Oct 26, 2011, 10:27:30 PM10/26/11

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DewDude wrote:
>
> explain your reasoning or stfu.

This isn't a gay dating newsgroup, so go away.

--
You can't have a sense of humor, if you have no sense.

et...@whidbey.com

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Oct 26, 2011, 11:25:55 PM10/26/11

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On Wed, 26 Oct 2011 13:12:54 -0700 (PDT), DewDude <dew...@gmail.com>
wrote:

PLONK

who where

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Oct 27, 2011, 9:39:29 AM10/27/11

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and put a pull-down on the MR pin - I use that same configuration (Q6
in my case) and a 10K pull-down helps remove any transient crap off
the output pin that just *might* cause a reset.. YMMV

Sylvia Else

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Oct 31, 2011, 7:38:58 PM10/31/11

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On 27/10/2011 7:12 AM, DewDude wrote:
>
> explain your reasoning or stfu.

That's a spectacularly foolish way of reacting in a newsgroup where
you're seeking help. Even those who are not the target of your response
are likely to take the view that you can go and play in the traffic.

Sylvia.