The Victor HC-90 is an MSX2 computer created in 1986 by JVC (Japan Victor Company). The HC-90 was manufactured for the Japanese market. It has a light-gray case and comes with a Japanese keyboard.

The HC-90 is equipped with dual CPUs:

• The Z80
• The Z180 for Turbo

Also on the front of the case are sliders for the audio, color enhancement and tint. The computer has built in superimposing and a frame grabber, and some models have a switch on the back of the computer to enable or disable the superimposing synchronization signal search.

There were several models of the HC-90, the HC-90, HC-90 A&B and the HC-90 V&T models. The A&B models had 64KByte of RAM, and used the V9938 VDP, while the V&T models came with 256KByte RAM and used the V9958 VDP. Other changes between the models were minor differences in circuitry and the addition of the synchronization search switch. A final model was produced, the HC-90 H with a built in 40MByte hard drive, meant to be used by Japanese Cable TV Operators for things like on-screen text in broadcasts.

• CPU and Memory
• Video Output hardware
• Audio hardware
• Cassette and Disk drives
• Keyboard, mouse and joysticks
• Expansion and I/O ports

MSX was a standardized home computer platform announced on June 16th, 1983 as a joint effort between Microsoft and Japan’s ASCII Corporation. It was marketed by Kasuhiko Nishi, who was Vice-President at Microsoft and a director at the ASCII Corporation, with the goal of creating a unified hardware and software standard across multiple manufacturers. At the time, the home computer market was highly fragmented, with each company offering its own incompatible systems. The MSX standard addressed this by providing a common architecture that companies like Sony, Panasonic, Philips, Toshiba, and Yamaha could all build upon, ensuring that software and peripherals would run consistently across machines. At its core, the MSX used the popular Zilog Z80 processor, featured cartridge slots for games and applications, and supported both cassette tape and disk drives, making it versatile for both gaming and productivity.

The MSX Standard defines specifications for:

• CPU and Memory
• Video Output hardware
• Audio hardware
• Cassette and Disk drives
• Keyboard, mouse and joysticks
• Expansion and I/O ports

The MSX line saw several evolutions, including MSX2, MSX2+, and MSX Turbo R, each improving graphics, sound, and performance to keep pace with the growing demands of the market. While it never achieved major success in the United States, the MSX was a significant force in Japan, much of Europe, and South America, where it became a beloved platform for gaming, programming, and creative applications. Iconic game developers such as Konami and Hudson Soft produced influential titles on the MSX, helping to shape the future of video games. Today, the MSX is remembered as one of the most ambitious attempts to create a universal home computer standard, and it holds a cherished place in the history of 1980s computing.

Cassette Interface

The MSX Standard calls for all MSX computers to have a standard data-cassette port. This port transports the audio-in/out signals to and from the datarecorder and the computer has a relay-switch on board to turn the recorder on and off.

MSX Cartridge

The MSX Cartridge system uses a 50-pin flat-edge connector to connect to the systems expansion bus. The cartridge slot maps into one of the main- or sub-slots.

MSX Joystick Port

The MSX Joystick connector is backwards compatible with the Atari 2600. It is a so called DB9 style connector and has the same pin-out as the original Atari connector, with the addition of an extra button. This port is also used in analog mode on the MSX to read a mouse, a light-pen or an analog joystick. The MSX Standard called for 2 joystick ports (Joystick A, and B).

Printer Port

The MSX uses a 14-pin Centronics port for connecting a printer. The printer port was not part of the mandatory MSX standard, but the standard strongly recommended manufacturers to implement a printer port.

Other Ports

Other mandatory ports on the MSX computer included a Composite Video or an RF output port for video. Many manufacturers also included an Audio port, a scart port on european models, the JP21 Scart variant for Japanese MSX computers, or an RGB port for better video connection to a monitor

The MSX2 Standard was introduced as successor to the MSX standard. The biggest improvement on the standard were the video capabilities of the system. Where the MSX-1 was quite capable with 16 colors and hardware sprites, it had some limitations. The graphics mode was pattern based, which meant that pixels were grouped by the 8, and each 8 pixels could only have one foreground and one background color. For games and pictures this meant that there was a color spill effect, colors bleeding over in unwanted areas.

The MSX2 introduced a new Video Display Processor, the V9938. This chip had the capacity to display 256 color simultanously, or have graphics modes with 16 colors out of a 512 color palette. It had true bitmapped graphics, that offered multiple in-memory pages for double buffering or vertical scrolling. The sprite system now supported multi-color sprites, and up to 8 sprites per scan-line. The Video RAM was defined to be at least 64KByte, but most systems came with 128KByte which was the maximum the V9938 supported.

The V9938 made it possible to create some great games. The most famous is the very first version of Konami's excellent game Metal Gear.

The V9938 is a video display processor developed by Yamaha. It is mainly used on MSX2 computers, but also in teh Tatung Einstein 256 and the Geneve 9640 enhanced TI-99/4A clone. Some MSX-1 computers used it with 16kByte of memory to enable a 80 column text display

Specifications:

• Video RAM: 16-192 KByte
• Text mdoes: 80x24, 40x24, 32x24 (with sprite capability and multi-color)
• Graphics: 512x212 (16 colors from 512), 256x212(16 colors from 512) and 256x212 in 256 colors
• Sprites: 32 sprites, 16 colors (2 per line), 8 sprites per scanline
• Hardware Accelleration for copy, line, fill and logical operations
• Interlacing for doubling of resolution
• Vertical scroll register
• Clock: 21 MHz
• Superposition and digitization capabilities
• Video Output: 15 kHz
• Support for lightpen and mouse<

The Z80 quickly became popular in the personal computer market, with many early personal computers, such as the TRS-80 and Sinclair ZX80, using the Z80 as their central processing unit (CPU). It was also widely used in home computers, such as the MSX range, SORD, and the Amstrad CPC, as well as in many arcade games. Additionally, it was also used in other applications such as industrial control systems, and embedded systems. The Z80 was widely used until the mid-1980s, when it was gradually replaced by newer microprocessors such as the Intel 80286 and the Motorola 68000.

The Z80 microprocessor was developed by Zilog, a company founded by Federico Faggin in 1974. The Z80 was released in July 1976, as a successor to the Intel 8080. It was designed to be fully compatible with the 8080, but also included new features such as an improved instruction set, more powerful interrupts, and a more sophisticated memory management system.

Originally the Z80 was intended for use in embedded systems, just as the 8080 CPU. But the combination of compatibility, superior performance to other CPUs of the era, and the affordability led to a widespread use in arcade video game systems, and later in home computers such as the Osborne 1, TRS-80, ColecoVision, ZX Spectrum, MSX, Sega's Master System and many more. The Z-80 ran the original Pac-Man arcade cabinet. The Z-80 was used even in the Game Gear (1990s), and the TI-81 and succeeding graphic calculators.

The Z-80 remained in production until June of 2024, 48 years after its original release. Zilog replaced the processor with its successor the eZ80, an 8-bit microprocessor that features expanded memory addressing up to 16 megabytes, and running up to 50MHz, comparable to a Z80 clocked at 150MHz.