Overview
ISO 8790:1987 - Information processing systems - Computer system configuration diagram symbols and conventions - defines a standardized set of graphical symbols and conventions for drawing computer system configuration diagrams (including automatic data processing systems). The standard establishes four levels of symbol detail (from high-level physical units to detailed device types), connection-line types, and reading/writing conventions to ensure diagrams are clear, consistent and unambiguous.
Key topics and technical requirements
- Scope and exclusions
- Applies to graphical representation of major hardware units and their connections.
- Does not cover detailed electronic or circuit diagrams, pictorial drawings, or mnemonic abbreviations.
- Symbol levels
- Four levels permit varying detail: Level 1 (physical enclosure), Level 2 (major units), Level 3 (basic media and I/O types), Level 4 (detailed device kinds).
- Physical unit symbols
- Generic symbols for processing/control units, storage units (main, direct access, sequential, mass storage), and input/output units (printers, displays, keyboards, card/tape units, audio, etc.).
- Connection lines and links
- Symbols and conventions for ordinary cables, bus connections, wired and wireless communication links, single- and multi-channel wireless links.
- Rules for bus closure, line crossings vs. junctions, arrows for direction, grouped connections, daisy-chain and star-burst layouts.
- Diagram conventions
- Recommendations on symbol shape, orientation, identification (names, mnemonics, model numbers), representation of multiple units in a single enclosure, overlaid units, repetitive/omitted units (ellipses), and future installations (dotted lines).
- Consolidated symbol table
- A combined reference showing symbol mapping across the four levels.
Applications
ISO 8790:1987 is practical for producing standardized, easy-to-read computer configuration diagrams used in:
- Technical specifications and procurement documents
- System architecture and network design diagrams
- Vendor brochures and product documentation
- Computer centre layouts and operations manuals
- Educational materials, textbooks, and magazine articles describing data processing systems
Who should use this standard
- System architects and network designers
- Technical authors and documentation teams
- Procurement and contract specialists preparing equipment specs
- Educators and trainers in information processing systems
- Standards implementers and reviewers ensuring consistency in diagrams
Related standards
- Prepared by ISO Technical Committee ISO/TC 97 (Information processing systems). Users should refer to the latest editions of related ISO standards for interoperability and updated symbol conventions.
Keywords: ISO 8790:1987, computer system configuration diagram, graphical symbols, connection lines, information processing systems, diagram conventions, configuration diagrams.