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Location:
Land of Oz
Registered:
June 2004
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Re: RMIT - computer course
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Wed, 27 July 2005 12:10
 
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Hi,
I assume you're referring to the 74163 Synchronous 4-bit counter?
If so, it's a 16-pin DIP integrated circuit. I use them quite often to reduce clock frequencies to a value that can be used by serial communicatiosn chips.
The low power Schottky version is the best one to use and it is the 74LS163.
Basically, you set up the chip enable pins and clear pins to ensure the device can count. Then you apply a frequency into the clock input pin. You have 4 output pins where the first pin is half, the next pin is a quarter, third pin is an eigth and the fourth pin is one sixteenth of the input frequency. For example, if you put 16Mhz clock into the chip the four output pins will output a frequency of 8Mhz, 4Mhz, 2Mhz and 1Mhz.
You also have 4 input pins that provide weighting for the output count. Notice 4 input and 4 output pins? That's why it's called a 4-bit counter. It doesn't do anything real fancy except divide clock signals. The modulo-16 is 'cos it counts 4-bits and 4-bits can count up to 16 (well, 0 to 15 actually, the 16th count gives a carry/ripple and the 4-bits go back to 0).
The ripple/carry bit allows you to cascade these bad boys together to get lower counts and to do 8-bit (if you put 2 chips together) or 12-bit (if you put 3 chips together) counting etc.
You can find the datasheet for this device at....
http://focus.ti.com/lit/ds/symlink/sn74ls163a.pdf
I hope this helps. If I've gone off on a tangent and totally off topic (as usual, but hey, I'm old so cut me some slack) then sorry and ignore this post.
seeyuzz
river
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| | Subject | Poster | Date |
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RMIT - computer course
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verbatim210 | Mon, 25 July 2005 22:53 |
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Re: RMIT - computer course
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Squid | Tue, 26 July 2005 00:19 |
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Re: RMIT - computer course
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b1gb3n | Tue, 26 July 2005 05:32 |
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Re: RMIT - computer course
|
Squid | Tue, 26 July 2005 05:58 |
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Re: RMIT - computer course
|
verbatim210 | Tue, 26 July 2005 13:33 |
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Re: RMIT - computer course
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b1gb3n | Wed, 27 July 2005 09:26 |
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Re: RMIT - computer course
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ShiRi | Wed, 27 July 2005 09:35 |
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Re: RMIT - computer course
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river | Wed, 27 July 2005 12:10 |
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Re: RMIT - computer course
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verbatim210 | Thu, 28 July 2005 03:45 |
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Re: RMIT - computer course
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b1gb3n | Thu, 28 July 2005 17:46 |
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Re: RMIT - computer course
|
verbatim210 | Thu, 28 July 2005 18:47 |
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Re: RMIT - computer course
|
b1gb3n | Thu, 28 July 2005 18:48 |
