Is there a counter cmos chip that does the following:

Hi,

I was wondering if there was a cmos / ttl chip available that would do
the following for me.

Has an internal 16 bit (or higher) counter
Has a count direction pin (count up / cound down)
Has an ouput pin that is high when the internal counter value is zero
Has a clock pin to increment / decrement count on leading edge

Some other information:
I do not need the internal counter value to be outputed
I don't want to string together a bunch of 4 bit counters with the
carry bits linked together.

Thanks for any information.

-M

 

[Anders F]

<munglet@hotmail.com> wrote in message
news:1110923416.177843.149900@o13g2000cwo.googlegroups.com...

Hi,

I was wondering if there was a cmos / ttl chip available that would do
the following for me.

Has an internal 16 bit (or higher) counter
Has a count direction pin (count up / cound down)
Has an ouput pin that is high when the internal counter value is zero
Has a clock pin to increment / decrement count on leading edge

Some other information:
I do not need the internal counter value to be outputed
I don't want to string together a bunch of 4 bit counters with the
carry bits linked together.

I know it's not what you're asking for... But if you don't find it (God
forbid), it's a classic uC task! ;-)

/A

Thanks for any information.

-M

 

[Don Lancaster]

munglet@hotmail.com wrote:

Hi,

I was wondering if there was a cmos / ttl chip available that would do
the following for me.

Has an internal 16 bit (or higher) counter
Has a count direction pin (count up / cound down)
Has an ouput pin that is high when the internal counter value is zero
Has a clock pin to increment / decrement count on leading edge

Some other information:
I do not need the internal counter value to be outputed
I don't want to string together a bunch of 4 bit counters with the
carry bits linked together.

Thanks for any information.

-M

It is called a PIC.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: don@tinaja.com

Please visit my GURU's LAIR web site at http://www.tinaja.com

 

[Roger Hamlett]

"Don Lancaster" <don@tinaja.com> wrote in message
news:39p6kkF62euinU1@individual.net...

munglet@hotmail.com wrote:
Hi,

I was wondering if there was a cmos / ttl chip available that would do
the following for me.

Has an internal 16 bit (or higher) counter
Has a count direction pin (count up / cound down)
Has an ouput pin that is high when the internal counter value is zero
Has a clock pin to increment / decrement count on leading edge

Some other information:
I do not need the internal counter value to be outputed
I don't want to string together a bunch of 4 bit counters with the
carry bits linked together.

Thanks for any information.

-M

It is called a PIC.
At low frequencies only though.

Best Wishes

 

I agree. An 8 pin PIC would do a fantastic job and that is probably the
route that I will go as it much more flexible, but overall I was just
wondering if there was such a chip that I described.

Thanks.

 

munglet@hotmail.com wrote:

Hi,

I was wondering if there was a cmos / ttl chip available that would
do
the following for me.

Has an internal 16 bit (or higher) counter
Has a count direction pin (count up / count down)
Has an ouput pin that is high when the internal counter value is
zero
Has a clock pin to increment / decrement count on leading edge

Some other information:
I do not need the internal counter value to be outputed
I don't want to string together a bunch of 4 bit counters with the
carry bits linked together.

It is a long time since I used the part (about 17 years), but Farnell
still seem to stock the LSI Computer Systems Inc LS7166 24-bit
multimode counter. It has got enough bits for your job, and definitely
does up- and down-counts under external control.

http://www.lsicsi.com/pdfs/LS7166.pdf

Unfortunately, I can't remember exactly how you read the beast - over
some kind of bus, if memory serves - and I've got no idea whether you
use the carry or borrow flags to do your job. It is a 15-page data
sheet, and I can remember that it was hard work to make sense of it.

Hope this helps.

--------
Bill Sloman, Nijmegen

 

Thanks Bill, I'll take a look at.

 

[Joerg]

I agree. An 8 pin PIC would do a fantastic job and that is probably the
route that I will go as it much more flexible, but overall I was just
wondering if there was such a chip that I described.

There probably is and I think Bill had one in mind. But if this is for a
series product I'd be careful not to design in a "boutique chip". Some
of these are high price and, most of all, could vanish from the market
rather quickly.

With uCs, the MSP430 does this nicely, too. It has a 16 bit timer which
can be clocked at a very fast clip.

Doing the carry thing ain't so bad either. Many 4 or 8 bit counters come
in TSSOP packages, even older ones. Really small.

Regards, Joerg

http://www.analogconsultants.com

 

[Mac]

On Tue, 15 Mar 2005 13:50:16 -0800, munglet wrote:

Hi,

I was wondering if there was a cmos / ttl chip available that would do
the following for me.

Has an internal 16 bit (or higher) counter
Has a count direction pin (count up / cound down)
Has an ouput pin that is high when the internal counter value is zero
Has a clock pin to increment / decrement count on leading edge

Some other information:
I do not need the internal counter value to be outputed
I don't want to string together a bunch of 4 bit counters with the
carry bits linked together.

Thanks for any information.

-M

Since no one else mentioned it, I'll just note that a PLD could also
handle this task easily, and could probably do it at higher speeds than a
microcontroller.

--Mac

 

[Paul Burke]

munglet@hotmail.com wrote:

Hi,

I was wondering if there was a cmos / ttl chip available that would do
the following for me.

Has an internal 16 bit (or higher) counter
Has a count direction pin (count up / cound down)
Has an ouput pin that is high when the internal counter value is zero
Has a clock pin to increment / decrement count on leading edge

You'll easily make one with a small CPLD, say a Lattice 1016 or a
Coolrunner 64 macrocell chip. Both have free programming software, the
coolrunner is a lot less thirsty.

Paul Burke