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This is the PC
Engine CD section. I have a small selection of PC Engine CD Games, as well as PC Engine
CD Consoles and
bits and bobs of hardware in the Hardware section. Click any of these links to take you to the appropriate
section.
The PC-Engine was the
first home video game console to offer a CD-ROM accessory, allowing the standard
benefits of the CD medium: more storage, cheaper media costs, and red book
audio. The efficient design, backing of many of Japan's major software
producers, and the additional CD ROM capabilities gave the PC Engine a very wide
variety of software, with several hundred games for the CD formats
The various CD-ROM game types are:
CD-ROM (pronounced CD-ROM-ROM) : Standard CD-ROM game.
Super CD-ROM : Requires a compatible system or upgrade card.
Arcade CD-ROM : Requires an upgrade card.
The PC-Engine CD-ROM peripheral had no built in RAM for storage of program code
and data loaded from the CD. With the exception of the Duo hardware series, all
RAM for the PC-Engine CD-ROM was contained on a ‘System Card’. A System Card was
a HuCard, which contained not only RAM, but also BIOS software for the PC-Engine
CD-ROM unit
While the standard CD-ROM and Super CD-ROM had RAM for data storage which was
accessed directly, the Arcade CD-ROM cards accessed the RAM in a slightly
different way.
Both the Pro and Duo versions of the Arcade Card worked in the same way. Just as
with the Super CD-ROM, up to 256KB of the RAM was able to be accessed directly
by the CPU. The other 2048KB was accessed indirectly by transferring data to the
other 256KB of RAM on the fly. This was done rather seamlessly, so that even
though the CPU could only use up to 256KB of RAM at once, data could be swapped
to and from the other 2048KB of RAM at any time.
This technique of
swapping data from RAM to RAM was much faster than loading the data directly
from the CD into RAM, and offered developers a significant advantage over the
previous System Card formats, as is evidenced by the many conversions of
well-animated Neo Geo fighting games to the Arcade CD-ROM.
One technique that was used by games pre-dating the Arcade Card upgrade was to
store graphics data in the 64K audio RAM (used for ADPCM samples) that was
present. This RAM could be directly populated by the CD-ROM hardware (it had a
direct DMA channel from the CD controller) without CPU intervention, and the
memory could be accessed in an indirect fashion, similar to the Arcade Card,
allowing data stored in it to appear as a 64K stream of linear data that could
be easily transferred to the system RAM.
NEC developed a prototype adaptor that connected a PC through the HuCard slot,
allowing the PC to control the PC Engine's CD ROM as it would any normal SCSI
drive. Due to falling CD drive prices and the increasing undesirability of a
single-speed SCSI drive, it was never released. It was however previewed in
NEC's official US TurboDuo magazine.
The PC Engine-CD was ultimately succeeded by the PC Engine Duo, which integrated
the CD drive and the main unit into one console.
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