630 Data Communication System

This document is a technical manual for the Digital Equipment Corporation 630 Data Communication System (DCS). The 630 DCS is a real-time interface designed to connect multiple teletype stations to a computer, facilitating applications such as time-sharing, message switching, and data collection.

Key components and features of the system include:

• 631 Data Line Interface: Handles signal level conversion between teletype stations and the computer.
• 632 Send/Receive Group: Contains mixers for character processing and service request flags, supporting various data rates and codes.
• 633 Flag Scanner: A modular system that scans service request flags. It allows for system expansion and supports priority-based handling of service requests.
• 634 Basic Control: Manages decoding of computer instructions and synchronization via a precision crystal-controlled clock.

The manual provides comprehensive details on system architecture, programming instructions for various computer models (PDP-1, PDP-4, PDP-5, and PDP-6), hardware installation considerations, and price lists. It also includes specific operational guidance for using Teletype Model 33 and 35 stations, including ASCII code mapping and character generation tables.