F15 PDP1 Handbook Apr60

This document describes the Programmed Data Processor-1 (PDP-1), a high-speed, solid-state digital computer developed by Digital Equipment Corporation, detailed in a 1960 publication.

Key features of the PDP-1 include:

1. Architecture: It is a single-address, single-instruction, stored-program computer with an 18-bit word length. It leverages five-megacycle circuits and a magnetic core memory.
2. Performance: Capable of 100,000 additions per second, it was significantly faster than many contemporary machines. Basic operations like add/subtract take 10 microseconds, while others like jump take 5 microseconds.
3. Hardware & Design: Built with DEC's System Building Blocks and saturating transistors, it emphasizes reliability and ease of use. It requires only conventional 110-volt power, no special air conditioning, and a relatively small footprint (32 sq ft). The Central Processor handles control, arithmetic, and memory addressing.
4. Memory System: It features a 4096-word magnetic core memory (18 bits per word) with a 5-microsecond read-rewrite time, and is expandable with additional modules and magnetic tape transports.
5. Programming: The PDP-1 supports advanced programming features such as multiple-step indirect addressing, Boolean operations, 12 types of arithmetic and logical shifts, and 10 conditional instructions. It uses a fixed-point binary number system, with subroutines available for decimal-to-binary conversion and floating-point operations.
6. Input-Output (I/O) Equipment:
   • Standard: Includes a photoelectric paper tape reader (300 lines/sec), an on-line typewriter for input/output, and a paper-tape punch (20 lines/sec). A special "Read-In Mode" facilitates initial program loading.
   • Optional: A wide range of optional devices can be added, such as magnetic tape systems, a real-time clock, a 16-inch Cathode Ray Tube (CRT) display for graphic output, a light pen for user interaction, a line printer, and analog-to-digital/digital-to-analog converters. The system is designed for easy integration of new I/O devices.
   • Sequence Break System: An optional interrupt system with up to 16 channels allows for concurrent operation of multiple I/O devices and the main program.
7. Manual Controls: The console includes indicator lights for all flip-flops, as well as toggle switches (Test Address, Test Word, Sense Switches) and push buttons (START, STOP, CONTINUE, EXAMINE, DEPOSIT, READ-IN) for manual operation, debugging, and maintenance.
8. Utility Programs: The computer is delivered with a suite of utility programs, including a Symbolic Address Assembly Program, memory print-out, binary punch/read-in, and maintenance routines. Later addenda mention an expanded set of utilities including a Compiler-Assembler, floating-point arithmetic system, and oscilloscope output routines.

The document also provides detailed instruction lists (arithmetic, logical, general, shift/rotate, skip, operate, in-out transfer) and alphanumeric codes used by the system.