Fred, a completely unrelated piece of information, but interesting nonetheless:
Elnec device programmers are very famous for the number of devices it programs and its robustness. Also for their clones. If you open a cloned beeprog you cannot differ it from an original beeprog. I still haven't completely reverse engineered the protection, but it seems to be related to the serial number. If any host software beyond 2.63 detects a "fake programmer" it BRICKS the cloned prigrammer. Yes, rends it useless. You gotta reprogram a pair of eeproms and a pic to make it work back again. You told about the prolok plus erasing hds and I remembered of this atitude from elnec. And no, I know of no one that sued elnec for bricking their clone programmer. So bad. They are great programmers, I have an old beeprog. 73 de pu2sex Alexandre Enviado do meu Tele-Movel Em ter, 2 de nov de 2021 17:35, Fred Cisin via cctalk <cctalk@classiccmp.org> escreveu: > On Tue, 2 Nov 2021, dwight via cctalk wrote: > > The trickiest protection I've seen is where there is a hole punched > > through the disk on one track. The idea is that the protected program > > writes to that track and expects to see a failure to read that track. > It doesn'tneed to be a hole all the way through, merely any physical > defect that renders that spot unusable. > > The "Physical Defect" protection. > > Copy protected disks had already been made with flawed content to produce > an error on READ, and were easily circumvented by the "duplicate" copy > having flawed content. The next step was to have a physical defect, so > that the protection software would WRITE to the bad track, and confirm > that the track really was damaged. > So, they would scratch the disk. > In the case of Prolok, the check to confirm a physical defect consisted of > writing all zeroes to that area; verifying all zeroes; writing all ones; > and verifying all ones. > > > Vault Corporation produced "Prolok" with a physical defect. To make it > MUCH MORE IMPRESSIVE to investors and clients, instead of a roomful of > people scratching disks with paperclips, they used a "laser fingerprint" > (use a laser, instead of a paperclip). > > Since they gave the same or similar subroutines, that checked for the > defect, to every client, it was cracked with software that would locate > that subroutine, and replace the subroutine call with NOPs or gut the > innards of the subroutine. The cracks were often posted on Compuserve. > (Vault sued Quaid software for "CopyWrite"/"RAMKEY") > https://casetext.com/case/vault-corp-v-quaid-software-ltd ) > > For "cloning" (pirating copies, often with the Central Point Option > board (flux hardware)), software was developed that would > identify the location of the defect, the cloner would then attempt to > scratch the disk at that location, and then the software would locate the > defect and juggle stuff around to put the content in the right place(s) > relative to the defect. > > > But, Vault Corporation wasn't satisfied until they shot themselves in the > foot with very high caliber rounds. > They announced "Prlok PLUS". W. Krag Brotby (chairman of Vault) said that > it would, if it detected a "fake" copy, wipe out the user's hard disk! > Even at the announcement of Prolok PLUS, the computer marketing > community was aghast and enraged. It doesn't take much to realize the PR > nightmare, and the legal liabilities for damaging a customer computer, > even if it was NOT a false positive! > > Ashton-Tate, the largest Prolok client for dBase III, and part > owner of Vault, immediately cancelled their contracts. And announced > that they had done so, that they had never used Prolok Plus, never would, > and no longer used Vault Corporation products. > Almost all of Vault's other clients follwed suit. > > Prolok Plus never made it to market! > 'Course the "word was out". Few people realize that it was NEVER > actually put to use. In fact some of the more idiotic newspaper "solve > your computer problems" columnists, when stumped, would actually speculate > "maybe your computer was attacked by an out of control copy-protection > program." > > > So, we ended up with a mythical monster, and the creator of that mythical > monster was vanquished. > > If anybody can document an actual existence of Prolok Plus, I would like > to hear about it. > > > There is little mention of it on the web, but: > > https://tech.slashdot.org/story/08/06/09/1927205/a-history-of-copy-protection > "Re:Ahhh, holes burned in disks (Score:5, Informative)" > > > https://books.google.com/books?id=9y4EAAAAMBAJ&pg=PA19&lpg=PA19&dq=prolok+plus+copy+protection+vault+corporation&source=bl&ots=9Y7SBcnFx9&sig=ACfU3U3JDSEI-QjLjMi1V_gWdPq8gaHrHg&hl=en&sa=X&ved=2ahUKEwjijpjCufrzAhX2TDABHXh2DBgQ6AF6BAgHEAM#v=onepage&q=prolok%20plus%20copy%20protection%20vault%20corporation&f=false > > https://www.pcjs.org/blog/2019/05/05/ > Kryoflux display of Prolok > > -- > Grumpy Ol' Fred >
