Sinclair ZX Spectrum Interface 1
The ZX Spectrum Interface 1, released in 1983, was an expansion unit that added RS-232 serial communication, a network system called "ZX Net," and support for the **ZX Microdrive**, a high-speed tape-based storage system.
Key Features
Ports: RS-232 serial port, ZX Net network supportStorage: Support for up to 8 ZX Microdrives
Networking: Allowed Spectrums to communicate with each other using ZX Net
Firmware: Added additional BASIC commands for Microdrive and serial communication
Sinclair ZX Spectrum Interface 2
The ZX Spectrum Interface 2, released in 1984, was designed for gaming, providing joystick ports and a cartridge slot for instant software loading.
Key Features
Joystick Support: Two Atari-compatible joystick portsCartridge Slot: Allowed for instant-loading software without the need for tapes
Compatibility: Supported only Sinclair-branded ROM cartridges
Why Were They Important?
Expanded Functionality: Interface 1 enabled storage and networking, while Interface 2 made gaming more accessible.First Steps in Networking: The ZX Net system allowed basic multi-user networking.
Cartridge Support: Though underutilized, the Interface 2 was Sinclair’s attempt at instant-loading software.
Legacy
The ZX Spectrum Interfaces 1 & 2 were notable attempts to expand the Spectrum’s capabilities. While the Interface 1 was used in business and education, the Interface 2’s limited cartridge library meant it was mainly used for joystick support. Today, both are sought after by retro computing enthusiasts.