Description

VHD means Video High Density and AHD means Audio High Density. This system, released only in Japan by JVC/Victor, is different from the LaserDisc system released by Pioneer. Instead of being on optical disc, similar to a very large CD-ROM it is more similar to a LP record. Just like a LP it had two sides, requiring you to swap the disc over. But unlike LP it had a caddy to protect the disc.

Various movies were released in Japan on VHD format, and VHD was also marketed for use with the MSX and Sharp X1. Compatible VHD players for the MSX and Sharp X1 have the VHDpc logo. Several games were made for this system.

Games such as VROOM, The Players Club and Alice in Chemical Reaction are written in an interpreted (intermediate) language and are recorded on the VHD itself. This requires the computer to have an interpreter for the VHD language and has implications as to the type of games that could be developed due to the overhead of an interpreted language. As such games were also developed that were specific to the MSX or Sharp X1 computers, but instead of writing the game onto the VHD, the game was provided on a system specific tape.

Youtube video about the history and operation of VHD

VHD hardware

VHD Interfaces for MSX

VHD Interface description

Used I/O ports are the following.

The connector on backside of the player is a standard DIN 13-pin.

The following table is the interface board decription for the Sharp X1 VHCpc controller interface VO-20PS. The MSX interface might have a similar design to control the same VHDpc compatible players. Taken from http://x1center.org/sdx1/sdx1_0.html

VHDpc players

VHD software for MSX

Only ten software titles are known to have been commercialised for MSX. Just like the VHD hardware they are very rare and only ever released in Japan.

• 2 VHD's - MSX2 required (was tested on a dual VHD system controlled by a HC-95 computer, but probably not commercialised)

Example

Thunder Storm LX-3 VHD

MSX program for Thunder Storm LX-3