PDP-1D-48 engrDrws

This comprehensive document set provides a detailed technical overview, assembly instructions, parts lists, wiring diagrams, and functional schematics for the PDP-1D-48 computing system and its External Memories & High Speed Data Control Assembly (PDP-1D-48-2).

The document is organized into several key sections:

1. Assembly Drawings (Pages 1, 12): Illustrate the physical layout and placement of various components within the system's cabinets, including power supplies, logic modules, and input/output panels. Detailed notes on drilling, component installation, and panel rework are provided.
2. Master Drawing Lists (Pages 2, 5, 7): Offer a comprehensive index of all sub-drawings and their titles, categorizing the system's functional blocks. Key areas covered include:
   • Control & Timing: General Control/Timing, Instruction Register & Decoders, MA, MB, IO & PC Transfer Logic, Program Counter, Clock, Cycle One/Zero & Defer Cycles, Special Cycles & LCH & DCH.
   • Memory: Memory Extension Control Type 15A, Memory Address Register, Memory Buffer Register, 16K Type Memory Assembly, Memory Bus Interface.
   • Arithmetic/Logic: Accumulator Control, SKP/SWP & Mid Inst BK Logic, SH/RO Logic Program Flag and Ring Mode, LCH & DCH Control, Restrict Mode & Memory Protection Logic, Automatic Multiply/Divide (including a High Speed Mul-Div Type 10 Rack).
   • Input/Output (I/O): Standard/Optional In-Out Transfer Control, In-Out Mixer (including Option #1 and wiring for IOT-IM components), IO Register, Reader Control, Punch Control, Typewriter Control, SCR Driver 823-RACK 11F, Taper Pin Panels & In-Out Plug for Optional Equipment, I/O Outputs (IOT – IO).
   • Sequence Break System (SBS): Type 20 Control, Priority Chain (including wiring R1A-R1D), Type 120 SEZ BRK Indicators, 3.3K Series Resistors for Indications, D-003 Diode SEZ BRK, and an 82 Ohm Terminator.
   • Interface & Support: Reader Punch Teletype Type Control, Switch Plate, AC/IO/MB/RDR Indicators, various Type Buffers and Drivers (e.g., MB1 1685 Drivers to IOT Outputs), and TW Lines.
3. Parts Lists (Pages 4, 6, 8-11, 13-14, 17, 66-71): Detail all components required for assembly, including cabinets, various specialized panels (operator control, indicator, relay), power supplies, memory assemblies, standard hardware (screws, nuts, washers, bolts, rivets, spacers, cable clamps), and specialized electronic parts (connectors, resistors, diodes). Material specifications, such as .063" thick #5052-H32 Aluminum for panels, are provided.
4. Circuit Diagrams/Schematics (Pages 15-43): Offer detailed electrical representations of the system's functional blocks, illustrating the interconnections and logic for components such as the Indicator Panel, Memory Address Register, General Control/Timing, Accumulator, I/O Transfer Control, Clock, Reader/Punch/Typewriter Controls, and various transfer logic circuits.
5. Wiring Layouts (Pages 44-59, 62-65, 72-119): Show the physical wiring connections between different modules and components, typically organized by rack locations (e.g., 1A, 1B, 1C, 2A, 2B, 2C, 3H, 3J, 3K, 11A, 11B, 11C, R1A-R1D). These include specific layouts for AC/IO/MB/RDR indicators, various buffers and drivers, and detailed wiring schedules for standard PDP modules using color-coded wires and taper pins.
6. Flow Diagrams (Pages 60-61): Illustrate operational sequences for "Cycle One" and "Cycle Zero & Defer Cycles," outlining the steps and conditions for various machine operations and instruction types.
7. Module List (Pages 120-123): Catalogs the basic electronic modules used throughout the system, such as inverters, NEG Diode NOR gates, pulse amplifiers, DUAL Flip-Flops, Set-Reset FFs, CAP-Diode Gates, and Binary-Octal-Decimal Decoders, specifying their types and quantities.

The document provides a comprehensive blueprint for the construction, wiring, and functional understanding of the PDP-1D-48 computer system.