Changes
/* Disc */ Corrected missing entry for the Argonauts 8K Sector Speedlock Copier
[[Category:Copy Protection]]
'''Speedlock''' is the name of a disc and cassette copy protection designed by Dave Looker ([[DJL]]) and Dave , David Aubrey-Jones. Earlier versions mentioned "DJL Software" later versions mentioned "Speedlock Associates"and Simon Berry.
Earlier versions mentioned "DJL Software", while later versions mentioned "Speedlock Associates".
== Cassette ==
The speedlock Speedlock tape protections in their Amstrad CPC versions only use 4 3 different types of encoding :
Speedlock type 1 2 (1984-1986):
*11 A Side Soccer
*Xevious
Speedlock type 3 4 (1900 baud) (1986-1988): *Arkanoid Revenge of Doh*Basket Master*Crazy Cars*Deliverance Stormlord II*Gryzor*Mercenary: Escape From Targ*Renegade (Hitsquad)*Road Runner*Robocop*Stallone Cobra*Tank*Target Renegade*Tarzan (specific Speedlock)*The New Zealand Story*World Games
Special speedlock : *Altered Beast,Nigel Mansell GP => the main code is protected by Speedlock v4 while the level data uses Speedlock v2.*Back To the Future IIIdetermine whether a game uses Speedlock v4 or v6,*Bad Dudes vs Dragon Ninja,*Batman check the Movie,*Fighter Bomber,*Guerrilla War,*Hammerfist,*Monty Python Flying circus,*Mutants 64k,*Ocean Beach Volley,*Operation Wolf,*Operation Thunderbolt,*P47 Freedom Fighter,*Rainbow Islands,*SDI (activision)*Shinobi,*Star control,*Stormlord,*Super Wonderboy in monsterland,*The Addams Family 128k,*The Ninja Warriors,*The Untouchables,*Turrican II The Final Fight,*Typhoon,*Wizball,baud rate with CSW2CDT.
Speedlock type 4 6 (1675 baud) (1988-until the CPC death):Note that level data may use either the Spectrum variant 2 scheme, or the Sinclair Spectrum one.
*Altered Beast
*Back To the Future III
*Bad Dudes vs Dragon Ninja
*Batman the Movie
*Darkman
*Fighter Bomber
*Guerrilla War
*Hammerfist
*Monty Python Flying Circus
*Mutants 64k
*Ocean Beach Volley
*Operation Wolf
*Operation Thunderbolt
*P47 Freedom Fighter
*Rainbow Islands
*SDI (Activision)
*Shinobi
*Star control
*Stormlord
*Super Wonderboy in Monsterland
*The Addams Family 128k
*The Ninja Warriors
*The Untouchables
*Turrican II The Final Fight
*Typhoon
*Wizball
*Cabal
*Midnight Resistance
Speedlock was also available in disc version.
One version called "[[8k Speedlock]]", relied on the fact that the CPC's hardware (specifically, the [[765 FDC|µPD765]] disk controller) could reliably read but not 8 Kbyte sectors even though it was typically only possible to store more than 6,250 bytes on 300 rpm double density diskettes. Attempting to write 8k an 8 Kbyte sector would cause the system to over-write its header block. It was written here that "the format was either devised or done on an Atari ST or an IBM PC compatible machine (since the CPC share with them the same FDC controler). The main difference being that an ST or PC can write more data per track than a CPC." This contains several inaccuracies. The Speedlock team in fact wrote the diskettes using diskette interfaces custom-modified for this purpose. Also, an Atari ST also has 6,250 bytes/track although used a WD1772 disk controller, while the PC has over time been based on a variety of formats (e.g. HD was 360 rpm 15 sectorsetc.) and controllers (e.g. NEC µPD765 or Intel 8272A or 82072A.