Eric Smith wrote: Why this? The loadable microprogram storage is my 2nd option, already have begun to build some out of old cache rams. As I already wrote, I've contacted the company that made my (now old, only supporting 5V Devices) parallel port programmer, and their boss decided to implement the algorithms for the chips in the library so taht I could use tem with that programmer. Last but not least, that where not the first programmer that I've build myself... An Atmega doesn't cost that much and the hardware is easy to build if you only support one family of chips and don't have too much pin drivers for many different voltages. Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741

Dave Caroline wrote: Wow, good find! Must be a different (earlier?) edition of the databook than the one I have.

On Thu, Feb 23, 2012 at 8:48 PM, Dave Caroline <dave.thearchivist at gmail.com> wrote: Now scanned the A version and the programming section http://www.collection.archivist.info/archive/DB/DB41_Cypress_CMOS/ Dave Caroline

I'ev heard the (IMHO mostly bogus) reasons for not releasing such information, and I can understand why it wouldn't be included in earlier databooks and then included in later ones (either because many customers are demandign it, or because they relaise there;'s no major risk in releasing it), but I cna't see why it would be removed form alter versions of the databook. Once the informatio nis out there, it's out there... -tony

Sue.w That's one of the rasone often given, but I conisder it to be somewhat bogus. I've got other ways of making an EPROM go flaky, or die. Applying 240V (or 115V AC to the pins gernally kills them. So will a large enough static zap. A lesser static zap will get them to fail some tim The way to make sure I program in correctly is to publsih the programmign algorithm. Then I will follow that,. Having to use a commercial pgrogramemr of a particuler model is not enough IMHO. Programmers can and do fail. If my programmed EPROMs stop behaving coreectly how do I know if the programmer has fialed if I am not sure what it's supposed to be doing? If I know the programming algorithm I can put an logic analyser o nthe pins of the device being programemd and see if it's being programmed correctly. Do you know waht the problem was? Too low a Vpp? Noise on the Vpp line (or Vcc when programming)? Incorrect programmign pusle width? In any case none of this would explain why a manufactuer would publish the programming algorithm and then remove it from later versions of the databook. If the algorithm is 'out there', somebody is going to find it ans use it. -tony

I was an engineer at Data I/O from 1981 to 1997 and made numerous visits to semiconductor companies. The semiconductor companies had a good business reason for limiting access to the programming algorithms. The customers expected the programmed PROMs to work over the entire temperature and voltage range for the life of their products. They also expected a minimal number of chips that failed programming. To achieve this, the semiconductor companies would work with leading PROM programmer companies so they could certify the programmer met there specs. If a customer programmed part with one of these devices, the parts should meet all the specs and the semiconductor would stand behind them. Data I/O would publish a "Wall Chart" listing the thousands of different parts their programmers would handle and what revision of software and hardware was needed. Sometimes the programming algorithm would change after the PROM was released. Some process change would require a longer pulse width or a voltage change. I remember one time National Semiconductor had several production lots of bipolar PROMs that had a poor yield with the current algorithm. National asked the leading programmer companies to rush an update to customers. National could do this with 4 or 5 programmer companies, it couldn't happen with an update to a datasheet and expect every programmer to be updated. Michael Holley -----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Eric Smith Sent: Saturday, February 25, 2012 12:41 PM To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: Fast Eproms CY7C291 Data? Tony Duell wrote: Sure, but they're not worried about *you*. They're worried about some random idiot, who *claims* to have followed the published algorithm, but somehow screwed up, and then wants to return an entire lot of EPROMs that he claims are of defective manufacture.

Michael Holley wrote: Thanks Good that the semiconductor Manufacturers published the Algorithms to write to their RAMs ... :-) Sorry, but the above is Nonsense in my eyes. If they publish the datasheets, thy could inform companies that produced the programmers anyways to reach the end users. Ther isn't any benefit when they hold the algorithms secret. Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741

Fred Cisin wrote: Yea, try asking this the manufacturers of GALs, CPLDs and FPGAs. Exactly the same thing. Nobody is telling you how the bitstream for an FPGA is to be build. Nevertheless, I want to use already obsolete technology for hobbyist use, but thy couldn't deliver the needed information ANYMORE, since they had no documentation for the parts anymore, at least at Cypress. The new owner of the EPROM facility don't even answered.. Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741

Your safety is distinctly secondary there. The relevant safety is _their_ safety, from liability suits. If they don't support user repairs at all, they have a more effective legal shield against idiots botching repairs and then blaming them. Calling it user safety is a CYA measure on their part. If more of the world had sane legal systems, this wouldn't be an issue. But a discouragingly large fraction of the world isn't sane in that regard. There's also another effect at work: not providing parts raises the bar. There are people who would attempt a repair given parts but, faced with no easy-to-obtain "correct" parts, will give up and get a new one rather than doing what you do and creating a suitable part or deducing which stock item already is suitable. /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mouse at rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B

On Mon, 27 Feb 2012, Tony Duell wrote: No, the reason for that is to exclude competitors from the marketplace. A full set of telephony standards costs millions of dollars, and that's not including the national variants that are almost exactly the same but have some small bit tweaked to make them incompatible. If you're part of the manufacturer's cabal, you're on the committee that writes the standards and you get free copies. If you're a startup trying to break into the market then $*&% you. Alexey

As a UK library card holder, can I ask you point me there? I did hit upon the BSI shop. Trying a few standards at random, the cost of a download seemed to be anything from ?18 to ?171 (the latter being BS 1363-1:1995). Some of the standards look like they are in multiple parts. So if you need to know eevrything about 13A moulded plugs, then you need to acquire 4 standards. That's perhaps getting on for ?800 (I didn't feel the need to check all four prices!). Antonio

Be careful... I've come across ICs where the full data sheet, needed to use the part in a normal circuit (and not, for example to program it before using it) is covered by an NDA. And in mine. If the hold the algorithm,s secret and soemthing doesn;t work (even if you are usign an apporved programmer) then you have no way of knowing what the problem is. And I am certain;y not happy with that. Surely the thing to do is to publsijh the inforamtion but make it clear it's not supported and that the IC is only gauranteed if you use the apporved programmer, If you build a porgrammer you're on your own. OK, some people will try to cheat. If it's a hbbyist with 1 or 2 ICs, the simplest thing is to replace them -- the first time. It's peanuts to the company to do that. The second time you start asking questions as to why he's so unlucky wen nobody else has problems. If it's a company that's progerammed afew thosand parts and is having problems, you send somebody round to demonstrate what htey are doing. And if they're not using an approved programmer, that;'s the end of it. -tony

On 02/26/2012 10:57 AM, Tony Duell wrote: They're worried about the idiot that builds a one-off programmer for use in production, and doesn't test it thoroughly, and then destroys hundreds or thousands of chips. And yes, that *does* happen. I've seen the evidence of it on two different occasions. And yes, the people involved did try to return the chips and claim that they were defective.

Of course there's a better way. I'm not sure there's a better way for someone who wants to do business in the USA today, though; I wrote a rant here, but on reflection it's probably inappropriate. About the best I've come up with: publish nothing officially but leak the data in some plausibly deniable way, so that it's not difficult to find for the likes of us here but is sufficiently dodgy-looking to scare off anyone contemplating depending on it in a corporate production environment? /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mouse at rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B

Fred Cisin wrote: The better way that is being used now is to embed the programming algorithm in the device itself, so you feed the data to it in a relatively non-critical way, and the device programs itself. For most current devices, getting the "programming algorithm", i.e., how to present the data and tell it to program itself, is not difficult. The other part that people complain about is not knowing the meaning of the programming data stream for a CPLD or FPGA., and only being able to get that data stream by using the vendor's proprietary tools. That's a different problem, and there are even more reasons for that than there were for not publishing programming algorithms.

How does this differ from the ifiot who designes a PSU which puts a 25V spike on the 5V rail at power up/power down (and yse I have seen a regualtor circuit which does that -- in a commercial bench PSU!) and then tries to cleim all your ICs were defective? Or the idiot who takes zero anti-static precautions and then claims yuor ICs are failing i nthe field a couple of months later? -tony

A bit of triva on how we got TV from the moon - more mechanical TV. http://www.hawestv.com/moon_cam/moonctel.htm Ben.