The Casio MX-15 MSX1 computer is the international version of the MX-10. THe MX-10 was introduced as the successor of the PV-16 with as goal: how small can we go.

In order to reduce the size of the computer, the tape interface was removed. This goes against the MSX standard, so Casio provided the FA-32 or FA-33 CMT I/F package that provided the computer with a tape interface.

Another goal for this computer was to lower the price point. MSX2 computers were coming out, creating a downward push on the price of MSX1 computers. The MX-10 had a cheap chicklet keyboard with rubber keys that made typing a crime.

By adding the KB-10 expansion unit, two cartridge ports and a printer port could be added to the computer.

The MX-10 was produced for the Japanese market, and for the international market Casio produced the MX-15

• 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 TMS9918 is a series of video display controllers (VDC) manufactured in 1979 by Texas Instruments, also refered to as 'Video Display Processor' (VDP). The TMS9918 and its variants were used in the ColecoVision, CreatiVision, Memotech MTX, MSX, NABU Personal Computer, SG-1000/SC-3000, Spectravideo SV-318, Spectravideo SV-328, Sord M5, Tatung Einstein, Texas Instruments TI-99/4, Casio PV-2000, Coleco Adam, Hanimex Pencil II, and Tomy Tutor.

Key Features:

• 256x192 pattern based color pixels per screen
• 16 different colors
• 8-bit memory mapped CPU interface
• No need for DMA, CPU can access VRAM
• 32 single color Sprites per screen (4 per scanline)

Variants:

• TMS9918A - 60Hz output, NTSC video
• TMS9928A - 60Hz output, YPbPr video
• TMS9929A - 50Hz output, YPbPr video
• TMS9118 - Different RAM than TMS9918A, otherwise identical
• TMS9128 - Different RAM than TMS9928A, otherwise identical
• TMS9129 - Different RAM than TMS9929A, otherwise identical

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.