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111

When CD-ROM games were first introduced, game developers didn’t take any measures to prevent users from copying them, for two main reasons: CD-ROMs could contain more data than most hard drives at the time; CD writers were rare, and extremely expensive. The Wikipedia page on CD-R gives some idea of the expense involved: in 1990, CD recording systems cost ...


47

We had some software delivered on a CD in which the vendor purposely put a defect on a specific track. If that defect wasn't there, the software could say it wasn't an original CD. Since defects are not copied, even on low level track copies, an exact replica could not be created.


37

We used to have to write our own video playback system, so each game did it differently. I worked on Microcosm for the SegaCD and if I recall we used a 16 colour palette for the video playback and had to create our own compression and decompression tools to keep the overall data bandwidth below 150KiB/sec. Later games used tricks like changing the palette ...


36

As far as I remember, this wasn't a CD, but (supposed to be) a Laserdisc, and he was using a Philips player (the movie contained several Philips machines). Laserdiscs were available in different sizes between 12 cm, which is like a CD and up to 30 cm (LP size). In a technical way, the movie screwed up, as Laserdisks were neither digital (they used an ...


28

suppose it's possible that the PlayStation audio format does have the required instruments, and then they added the few repeated audio samples on top of that in the game engine There are no instruments "built into" the PlayStation. Games provide their own. The PlayStation sound chip is basically a 24-channel ADPCM playback with 512KB of sample ...


23

(preface: While Stephen's answer already covers the basic points, I would like to put a different emphasis here - and merge in some private history :)) Short answer: It was the game's size and the need to copy it to a CD again, combined with expensive and unreliable writers. Further, the CD itself was used as a copy protection. While games often got ...


18

Just a disclaimer: Most of this is based on observation and assumptions from experience and should be taken with a grain of salt. From what I've seen with this glitch, the audio being played is actually just a very stretched out version of the chimes that play over the second logo which you see when a disc is loaded, rather than a separate sample. Judging ...


17

Playback of compressed digital video is handled entirely in software on the Sega CD which is why FMV games on it play with the video taking less than the full screen and at relatively low frames per second. It doesn't contain any dedicated decoding hardware. It does contain a faster processor (12.5MHz 16-bit Motorola 68000, 5MHz faster than the base Sega) ...


15

That is a Philips VP415 LV-ROM player.


13

TL;DR; Yes and yes, but. CD-ROM Mode 2 offers all 2336 bytes of a CD-ROM block for user data. By default all CD-ROM drives can read Mode 2 disks as well Mode 2 CD-ROM have been produced, but it never really took off. Mode 2 is not raw, but still incorporates basic error correction. Background: CD-ROM has error correction so that in the event of a slightly ...


13

Well, a few users are creating compilation of games for the CD32 and the CDTV. The most prolific is AmigaJay. For instance here he released several compilations for CDTV including a lot of titles: Volume 1 Volume 2 Volume 3 Volume 4 Volume 5 Volume 6 Basically, the compilations boot with a menu (AGS or other) then run scripts to assign volumes and boot ...


13

It's probably not exact but Sony back in the day had a really cool way of Protection against pirates: Simply said they changed the CD itself... and made it "Wobble" in a certain way in the beginning so the reader knew it's an OEM Disk.


11

In addition to Stephen Kitt's answer: Copy protection existed long before CDs; most of these techniques could be applied to CD-ROMs too. Many games that were shipped on floppies had copy protection - sometimes a question in the beginning that asked you to look at the booklet it came with, Monkey Island had a disk with 2 parts that you needed to set ...


11

A stock Amiga 500 doesn't come with any expansion port that would take a standard CD ROM drive (or hard disk) directly. Storage extension is limited to external floppy drives. The option of the day was to obtain an A570 1, a rather bulky interface that fitted to the A500 expansion port, which contained quite a bit of circuitry (DMA, ROMs containing the new ...


11

Physically, the Panasonic and Mitsumi interfaces are identical to unkeyed ATA interfaces, and 40-pin unkeyed IDE cables can be used to connect Panasonic and Mitsumi drives to a compatible controller. The Sony interface is based on the 34-pin floppy interface instead. In terms of signalling, according to AllPinouts the Mitsumi and Panasonic pinouts are the ...


11

It's a PSF (Portable Sound Format, see Wikipedia) music file, the PlayStation equivalent of the Amiga's module (.mod) format, where sound samples and replay data sequences are stored inside one file, so tracked music instead of streamed music.


10

Hardware-wise, you can get HiSoft's Surf Squirrel PCMCIA-to-SCSI adapter and attach an external SCSI CD-ROM drive. For this, you don't need to open up the A1200, but then you can't use the PCMCIA for a network card at the same time. Note the following caveat: The surf squirrel does not support auto-booting from a cold boot (power cycle) however drivers can ...


9

Because the PS1 has a very small amount of RAM, and sophisticated games, especially those on linear tracks like Crash Bandicoot, would load new data from the disc continually as the player traversed the level, replacing the data in RAM that was already there. When the player dies and reappears at an earlier location, the level would have to be reloaded from ...


8

A quick review of the games consoles suggests that the Saturn and PlayStation were the first to implement copy protection as a firmware-level feature; between the 3DO, Mega CD and PC Engine there are some measures to ensure games are from licensed developers but no built-in protection against copies. I was also unable to find any evidence of software for ...


8

Why would you think that you need a single speed writer to write a CD for a single speed drive? With an ideal writer, and ideal media, the resulting CD would be the same, no matter at which speed it was written. But the process of writing a CD is analog -- a laser beam locally changes the chemistry of the CD -- and faster writing means applying more energy ...


7

There's reason to believe that this is a qemu bug (actually a problem caused by the configuration of SeaBIOS in qemu 3.0 and 3.1). If this is the case, the CD driver will work fine in qemu 2.12.1 or older (SeaBIOS will be 1.11.1 or older), or qemu 4.0.0 or newer (SeaBIOS will be 1.12.1 or newer). A qemu displaying a SeaBIOS version of 1.11.2 or 1.12.0 will ...


7

The data here is a bit unclear what the mentioned measurement of 'hits' is about and where the percentage of 5 or 50 comes from. The whole setup doesn't give much information. Lets try to see what it could mean in relation to real world numbers. CD-Drives are usually not rated in 'hits' but MTBF hours, like most machinery, often amplified by duty ...


7

To answer the first half of your questions: The right-side 60-pin expansion slot is bespoke, and found on Mega Drive / Genesis 1 and 2 only. It is not present on the Genesis 3 or Nomad. It exposes the address and data buses and a lot of other signals. In that respect it's very similar to the 86-pin expansion slot on the left side of an Amiga 500 (and the 56-...


6

Due to the nature of optical media, the answer is probably whatever format lets you play the game as close as possible to how the original was. Optical media can have many "out of band" features, that is things that are not part of the raw data stream encoded on the disk. Often they can only be read by specific drives, and in some cases only the special ...


6

I think your premise is a bit off. Compression (lossy or otherwise) makes media much more susceptible to errors, not less. If you flip one bit in an uncompressed image, the probable result is that one pixel of the output is incorrect. If you flip one bit in a compressed image, the probable result is something like this. If you flip one bit in a video file ...


5

Besides the measures against copying the CD-ROM there were other things. Pretty popular were dongles: specific hardware devices put one the parallel port. The game (or other software) did not run without those dongles. The dongles could not be copied easily.


5

Firstly, many old computers had problems with booting from CD; It was either unsupported or very buggy. Secondly, even if booting from CD would work on that particular Aptiva, i doubt that booting from a recorded CD would - it has something to do with the way data is written to the disc (many pre-1997 (the year recordable CDs were introduced) CD-ROMs have ...


5

Try to approach the classification differently: 1) The CD-DA standard defined an audio sector of 2352 bytes. 2) The CD-ROM standard took 16 bytes from this sector for a 4 byte header and 12 sync bytes. The header allowed random access to this sector (which didn't work precisely enough for audio sectors). 1 byte of the header was for the mode. Mode 0 ...


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