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Author Topic: 1hz clock  (Read 3325 times)
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an ATtiny and an external 8 or 16 Mhz crystal could do it (Set it up to pulse every second)
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I am going to end this topic and start a new, more specific one. Thanks for all the help!
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Yes,
Feed 64 KHz into CCLK, RCO from stage 1 into stage 2, RCO Pulse from will yield a low going pulse 1/64K wide 1x a second.

http://www.eetkorea.com/ARTICLES/2001SEP/2001SEP06_AMD_AN.PDF
See figure 3 for suggestion on getting 64KHz source. Other ways also possible, this seems pretty straight forward.
http://www.z80.info/uexosc.htm
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Quote
seems pretty straight forward.

Not as easy as I would have hoped, but I guess it will be fine. For the first link, they don't specify where the output is...any ideas?

Also, is there a way I can get 50% duty cycle?
« Last Edit: May 25, 2011, 04:45:23 pm by baum » Logged

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Enable the outputs, and use the MSB, which will change hi/lo/hi/lo every 1/2 second.
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right...

how exactly do I setup the crystal though?
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I want to connect the 65.536kHz crystal to the clock of a binary counter. no microcontrollers involved.
Thanks!
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Reply #24 has circuits to make the 64K oscillator that will drive the clock line.
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But which would should I use? There are three on that page.
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My counter chip is a 74393, i will be running the power supply at 3V (2x AA) and I will be using this crystal.
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Whoops. Then how about 3x AA, which would be 4.5V?
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Whops again.... I meant to say 74HC393. smiley-sad Sorry for the confusion!
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Try the simplest one first baum, if that works then you're all set.
If not, try another.
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So the second one w/ 3 inverters and a 100N cap?
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I would have suggested Figure 3 from this link first
http://www.eetkorea.com/ARTICLES/2001SEP/2001SEP06_AMD_AN.PDF
1 inverter, couple of 22pF caps, couple of resistors.
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