Changes

However, only the The '''Spectrum''' and '''Commodore''' versions seem to have been actually released, but - as far as known - the Amstrad version wasn't ever released. According to the Oliver Twins (the makers of the CD), the '''Amstrad CPC''' hardware did exist, too. Though this seems to have been only an unreleased prototype. == Pictures == <gallery>File:TheCdGamesPackForSpectrum128.jpg|Spectrum 128 versionFile:CodemastersCDforC64.jpg|Commodore 64 versionFile:NoPicture.gif|Amstrad CPC versionFile:NoPicture.gif|Inside of plug/cableFile:OliverTwinsCodemastersCD.gif|Info from http://www.olivertwins.com/File:CodemastersCdOriginalCable.jpg|Cable Connectors</gallery>

The above circuit was rev-engineered by measuring the resistance between the cable pins, but without opening (=destroying) the moulded plastic connector that houses the original circuit - so far, it isn't fully confirmed if the original cable does really contain the above components (not to mention that multimeter tests can't reveal any additional small capacitors).

'''You are welcome to add your own results here if you like to combine research with some minor destruction!'''

* For kempston:Bit 4 (joystick fire) (pin6 on a atari-style kempston port) of port &1f is data.

* For sinclair: Bit 4 1 (joystick fireright/key '2') (pin6 on amstrad's non-atari-style spectrum +2 joystick port) of port &1f f7fe is data.

For sinclairThe loader is patched according to the interface chosen and appears to be a modified version of the normal cassette loading functions in the Spectrum BIOS.It seems to load the standard tape data structure:pilot, sync byte, data bytes and checksum byte. The loader uses only 1 bit (mono).

Bit 1 The CD capacity is said to be "12 Megs" (joystick right/key '2'presumably meaning 12 Megabit = 60 tracks with 25Kbytes each) of port &f7fe is data.

The loader is patched according to the interface chosen and appears to be a modified Spectrum ROM loader.It seems to load the standard tape data structure: pilot, sync byte, data bytes and checksum byte. The cable is most likely to be mono, because only 1-bit is used for loading. No info if/how the stereo signal is used. The cable does reportedly contain a 1bit A/D converter, which is probably a single transistor or so (so it's mono, not stereo?). The CD capacity is said to be "12 Megs" (presumably meaning 12 Megabit = 60 tracks with 25Kbytes each). It is more quite probable that the Amstrad loader is similar to the Spectrum loader:

* http://www.kjthacker.f2s.com/docs/audiocd2.html - DIY - '''caution:''' the disclaimer on that webpage says that it is '''not''' based on the real Codemasters CD - so it may be totally incompatible to the original Codemasters CD - also, Kevin has confirmed that it's an '''untested''' and '''unfinished''' DIY project * http://worldofspectrum.org/ - has a review about the Spectrum version - which conflicts with the DIY info (the Spectrum review implies it contains a mono 1-bit A/D converter, not a stereo connection without A/D converter) (the A/D converter - if it does exist - might refer to something simple, like a transistor)

* http://www.speccy.org/trastero/cosas/JL/CableCD/CableCD.html Testing Rev-engineering the wire of the CD Games Pack for Spectrum. Whether or not the Amstrad CPC version was actually released is a bit unclear. Did anybody ever see it for real? == Pictures == <gallery>File:TheCdGamesPackForSpectrum128.jpg|Spectrum 128 versionFile:CodemastersCDforC64.jpg|Commodore 64 versionFile:NoPicture.gif|Amstrad CPC versionFile:NoPicture.gif|Inside of plug/cableFile:OliverTwinsCodemastersCD.gif|Info from http://www.olivertwins.com/File:CodemastersCdOriginalCable.jpg|Cable Connectors</gallery>