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stevem
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Write Only Memory

10/21/2008 3:07 PM

Anyone know where I can find one of these?

http://www.national.com/rap/files/datasheet.pdf

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Bill
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#1

Re: Write Only Memory

10/21/2008 3:20 PM
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user-deleted-1105
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#2

Re: Write Only Memory

10/21/2008 4:35 PM

I'll send you an address on April 1st.

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DVader1000
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#7
In reply to #2

Re: Write Only Memory

10/22/2008 1:50 AM

Doesn't KrisDel sell them?

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user-deleted-1105
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#8
In reply to #7

Re: Write Only Memory

10/22/2008 2:28 AM

Only to gullible select customers.
Del

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Epke
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#3

Re: Write Only Memory

10/21/2008 10:57 PM

WOM'S no mistakes allowed? like OTP programing? stay with EEPROM'S it's easier

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Just an Engineer
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#4

Re: Write Only Memory

10/22/2008 12:09 AM

We used to make them and sell to FBI and other US agencies. Something about "eyes only" but "never to be released" information.

The WOM had infinite storage capacity, guaranteed never to be able to be read and could operate at any clock speed that was available.

I'm sure I've still got access to a couple of the parent chips and still know the mods to make them for you.

How many do you want?

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aamersyed
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#5

Re: Write Only Memory

10/22/2008 12:23 AM

check out this link

http://www.google.com/search?hl=en&q=http%3A%2F%2Fwww.national.com%2Frap%2Ffiles%2Fdatasheet.pdf&btnG=Google+Search&aq=f&oq=
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Turbotroll3
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#6

Re: Write Only Memory

10/22/2008 12:43 AM

AHHH YESS! The WOM or "Bit Bucket" chip. A friend of mine actually designed one of these into a circuit back about '81 or '82? It was the end device in a long counter chain that accepted the carry bit from the MSB counter.

The design went all the way through until purchasing could not find a source for the chip. Then they couldn't find a second source and the design was rejected because of a requirement for no sole source devices!

National Semi just laughed at the purchasing lady but never told her anything except that they were out of stock with no firm date for resupply. I suppose they had had more than a few requests by then.

The redesign was simply to not stuff U13. When the board was re-laid out in the next rev, "U13" was deleted. 8)

I always thought the chart showing pins remaining per socket insertion/extraction cycle was a nice touch.

Have FUN!

TT3

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PWSlack
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#9

Re: Write Only Memory

10/22/2008 2:56 AM

Try Stinky Pete.

Word has it that Turbo Encabulators are also available from this source.

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Randall
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#10

Re: Write Only Memory

10/22/2008 3:31 AM

Maybe one of these would do:-

http://www.topline.tv/catalog/topline_catalog.html

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user-deleted-1105
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#11
In reply to #10

Re: Write Only Memory

10/22/2008 3:51 AM

GA, KrisDelTM have expensive extensive test gear available for these products.

Del

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Qqberci
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#13
In reply to #11

Re: Write Only Memory

10/22/2008 8:32 AM

I can provide a write protecting appliance for additional 15 %...

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stevem
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#14
In reply to #10

Re: Write Only Memory

10/22/2008 9:07 AM

Thanks for the source. Now I can start building that TBit, First In Never Out buffer the NSA ordered.

The second mouse gets the cheese.

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Andy Germany
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#12

Re: Write Only Memory

10/22/2008 7:48 AM

Someone is pulling your leg!!! Its a joke.

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Bayes
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#15

Re: Write Only Memory

10/22/2008 9:30 AM

I've never seen a faucet on a circuit diagram before......innovative. All I need is a 6 foot fan and help figuring out where I land on the slow pay customer curve and I'm in business.

Good stuff.
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Randall
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#16
In reply to #15

Re: Write Only Memory

10/22/2008 9:50 AM

It's not a faucet it's a Test Access Pin.

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Bayes
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#17
In reply to #16

Re: Write Only Memory

10/22/2008 9:59 AM

my bad.
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user-deleted-1105
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#18
In reply to #17

Re: Write Only Memory

10/22/2008 10:06 AM

The tap is to allow you to wash your hands of the entire thread.

Del

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Bayes
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#19
In reply to #18

Re: Write Only Memory

10/22/2008 10:57 AM

I'm not an electrical engineer, I get confused with all these technical terms.
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silvCrow
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#20

Re: Write Only Memory

10/22/2008 4:49 PM

I have a whole tube of these for sale. These are rare and expensive, but I can save you some money. All you need to do is remove the output pin(s) from your regular memory and there you have it.

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Users who posted comments:

aamersyed (1); Andy Germany (1); Bayes (3); Bill (1); DVader1000 (1); Epke (1); Just an Engineer (1); PWSlack (1); Qqberci (1); Randall (2); silvCrow (1); stevem (1); Turbotroll3 (1); user-deleted-1105 (4)

Previous in Forum: Part P multi-testers for 16th & 17th edition tests   Next in Forum: Circuit mayhem and restless nights

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