The Telematico NMS3000 – Celso Martinho

7 hours ago

The Philips Telematico NMS3000 is a vintage Videotex terminal from 1988, designed for the Italian Videotel service.
Videotex was an early two-way electronic communication system using telephone lines, precursor to the internet.
The terminal's hardware includes a Z80 CPU at 3MHz, 32K ROM, 4K RAM, a Videotex decoder, and a built-in modem.
Initial challenges involved powering it without documentation, using a modified ATX supply and custom cables.
Connecting to a modern Mac via USB modem required simulating telephone line voltage to trick the modems.
Communication issues led to reverse-engineering the device and creating schematics using KiCad.
A macOS bug caused parity problems, fixed by manually calculating and sending parity bits in software.
A Videotex server was built using Cloudflare Workers, with a web-based terminal for testing.
The ROM was dumped, translated to English, and replaced with a modern One ROM emulator for flexibility.
Future enhancements include USB keyboard adapters, serial ports, and custom Z80 game development.

Hasty Briefsbeta