1 Digital Equipment Corporation Maynard, Massachusetts mamDomo Reference Manual ;1 PDP-15 Systems - DEC-15-BRZA-D PDP-15 SYSTEMS REFERENCE MANUAL DIGITAL EQUIPMENT CORPORATION 0 MAYNARD. MASSACHUSETTS 1st Printing August 1969 Copyright © 1969 by Digital Equipment Corporation Instruction times, operating speeds and the like are in­ cluded in this manual for reference only; they are not to be taken as specifications. TABLE OF CONTENTS Chapter Page General Description Introduction 1-1 PDP-15 Highlights 1-1 Summary of PDP-15 Characteristics 1-2 2 PDP-IS System Organization Central Processor 2-1 Memory 2-1 I/O Processor 2-1 System Peripherals 2-3 3 Organization of the Central Processor Summary of Characteristics 3-1 Central Processor Description 3-1 Processor Expansion 3-4 4 Memory Organization Summary of Characteristics 4-1 Core Memory 4-1 5 Organization of the Input/Output Processor Summary of Characteristics 5-1 I/O Processor 5-1 Addressable I/O Bus 5-7 Program Interrupt Facility 5-9 Automatic Priority Interrupt 5-10 Common I/O Bus 5-12 IOP1, IOP2, IOP4 5-13 6 Addressing Interpretation of Words From Memory 6-1 Information Retrieval From Memory 6-1 Memory Reference Instructions 6-2 Bank Mode Addressing 6-5 Nonmemory Reference Instructions 6-5 Operate Instructions 6-5 Data Words 6-6 Basic Software Floating-Point Formats 6-7 Boolean Representation 6-8 iii TABLE OF CONTENTS (cont.) Chapter Page 7 Instruction Repertoire Instruction Groups 7-1 Transfer Instructions 7-3 Arithmetic Instructions 7-3 Logical Instructions 7-4 Rotate Instructions 7-S Control Instructions 7-S Jump Instructions 7-7 Index and Limit Register Instructions 7-9 Register Control Instructions 7-10 Microcoding 7-11 Input/Output Instruction Group 7-13 8 Internal Options Instruction Set EAE 8-1 Basic Shift Instructions 8-4 Normalize Instructions 8-6 Arithmetic Instructions 8-7 Automatic Priority Interrupt Instruction Set 8-13 Memory Parity 8-lS Real-Time Clock 8-16 Power Failure 8-16 Memory Protection Option 8-17 Memory Relocation and Protect KT IS 8-19 The Hardware 8-21 9 Peripheral Options Standard Input/Output Devices 9-1 Mass Storage Devices 9-1 Line Printers and Plotters 9-3 Data Communications Devices 9-3 Display Devices 9-4 Interprocessor Buffer Systems 9-S Analog-to-Digital Converters 9-S Digital-to-Analog Converters 9-6 Operational Amplifier, Type AH03 9-6 I/O Bus Adapter, Type DWIS 9-6 10 PDP-IS Console Information/Control Switches 10-1 Operate Control Switches 10-3 Special Switches 10-4 Indicators 10-4 iv TABLE OF CONTENTS (cont.) Chapter Page 11 System Software PDP-15/10 Compact Software System 11-1 PDP-15/20 Advanced Monitor System 11-2 Common PDP-15 Software 11-3 PDP-15/40 Disk-Oriented BACKGROUND/FOREGROUND System 11-7 Additional Systems Software 11-7 Diagnostics 11-9 Appendix A Installation Planning Physical Configuration A-I Placement of Options A-I v PDP-15 FAMILY OF MANUALS HARDWARE SOFTWARE INSTALLATION ACCEPTANCE OPERATORS TE ST GUIDE MANUAL PROCEDURES MODULE INTERFACE MANUAL MANUAL ~. UTILITY PROGRAMS MANUAL MACRO -15 FORTRAN nz:: FOCAL -15 8/15 TRANSLATOR 15-0040 SYSTEM REFERENCE MANUAL - Overview of PDP-15/10 SOFTWARE SYSTEM - COMPACT VOLUME 3, PERIPHERALS (Set of Manuals) - PDP-15 hardware and software systems and op­ software system and BASIC I/O Monitor system Block diagram and functional theory of operation tions; instruction repertoire, expansion features descriptions. of the peripheral devices. Preventive and correc­ and descriptions of system peripherals. tive maintenance data. USERS GUIDE VOLUME 1, PROCESSOR - PDP-15/20 ADVANCED Monitor Software Sys­ INSTALLATION MANUAL - Power specifica­ Principal guide to system hardware includes sys­ tem - ADVANCED Monitor System descriptions; cations, environmental considerations, cabling tem and subsystem features, functional descrip­ programs include system monitor and language, and other information pertinent to installing tions, machine-language programming consider­ utility and application types; operation, core or­ PDP-15 Systems. ations, instruction repertoire and system expan­ ganization and input/output operations within sion data. the monitor environment are discussed. ACCEPTANCE TEST PROCEDURES - Step-by­ step procedures designed to insure optimum VOLUME 2 PERIPHERALS - Features function­ PDP-15 Systems operation. tiona I descriptions and programming consider­ PDP-15/30 BACKGROUND / FOREGROUND ations for peripheral devices. Monitor Software System - Background/Fore­ ground Monitor description including the asso­ ciated language, utility and applications pro­ MODULE MANUAL - Characteristics, specifica­ tions, timing and functional descriptions of mod­ grams. OPERATOR'S GUIDE - Procedural data, includ­ ules used in PDP-15 Systems. ing operator maintenance, for using the oper­ ator's console and the peripheral devices asso­ ciated with PDP-15 Systems. -< .-..-.. INTERFACE MANUAL - Information for inter­ PDP-15/40 Disk-Oriented BACKGROUND/ facing devices to a PDP-15 System. FOREGROUND Monitor Software System - PDP-15/10 SYSTEM USER'S GUIDE - COM­ Background/Foreground Monitor in a disk-ori­ PACT and BASIC I/O Monitor operating proce­ ented environment is described; programs include dures. language, utility, and application types. UTILITY PROGRAMS MANUAL - Utility pro­ grams common to PDP-15 Monitor systems. PDP-15/20 SYSTEM USER'S GUIDE - Advanced monitor system operating procedures. MAINTENANCE MANUAL VOLUME 1, PRO­ MACRO-15 - MACRO assembly language for the CESSOR - Block diagram and functional theory PDP-15. of operation of the processor logic. Preventive and corrective maintenance data. PDP-15/30 SYSTEM USER'S GUIDE - Back­ ground/Foreground monitor system operating FORTRAN IV - PDP-15 version of the FOR­ procedures. TRAN IV compiler language. VOLUME 2, PROCESSOR OPTIONS - Block PDP-15/40 SYSTEM USER'S GUIDE - Disk­ diagram and functional theory of operation of FOCAL-15 - An algebraic interactive compiler­ oriented background/foreground monitor system the processor options. Preventive and corrective level language developed by Digital Equipment operating procedures. maintenance data. Corporation. PDP-iS System viii FOREWORD PDP-IS Systems offer comprehensive solutions cations programs and special peripheral device to real-time data problems. They combine new handlers without forcing him to become a sys­ design concepts with a wide array of traditional tems programmer and (c) a system that can features that spring from Digital's years of expand naturally with any additional hardware leadership in the medium-scale scientific com­ the user purchases. PDP-IS Systems software puter field. Both elements share the common allows the user to move from a very basic purpose of simplifying the user's tasks in a machine to a sophisticated system environment demanding real-time environment. without the cost and complication of repro­ gramming at each upward step. Since certain types of data-handling tasks re­ The hardware systems were designed with sever­ quire specific hardware and software configura­ al functional objectives in mind. Among these tions, Digital has developed four standard are the complete autonomy between central PDP-IS Systems, ranging in power from the processor, input/output processor, and memory, modestly priced basic PDP-IS / I 0 to the real­ so that processing and I/O operations can occur time disk monitor environment of the concurrently in overlapping cycles; TTL PDP-IS/40. At every level, the capabilities of the integrated-circuit construction for high relia­ hardware are under the control of a monitor bility; fast internal speeds, including an 800-ns designed specifically for them. memory cycle time, to meet the demands of real-time data processing; core memory expan­ The software systems were designed around the sion to 131,072 words for future growth; and a hardware with the user environment in mind. sophisticated memory-protect system for multi­ The principal design objectives were to provide user integrity. Peripheral device handling and (a) a system that is convenient for the user to interfacing to other instruments are easily implement and that affords the user access to accomplished, and system growth potential is the full power of the hardware, (b) a system virtually unlimited with the modular structure that allows the user to easily integrate his appli- of PDP-IS Monitor systems. ix I SYSTEM DESCRIPTIONS Users are spared the task of writing system software to handle input/outputs to all standard system peripherals, since appropriate routines PDP-IS/1O: Basic System are supplied with the monitor. The net result is that even inexperienced computer users can get The PDP-IS II 0 is the first level PDP-IS System. their applications programs "on the air" in a The system's design provides limited budget minimum of time. users access to the power, speed, and 18-bit word length of PDP-IS hardware, in the expec­ PDP-IS /20 hardware facilities include not only tation that the system can later be expanded to 8,192-words of core memory and high-speed take full advantage of the advanced software paper-tape facilities but also a DECtape control capabilities inherent in the system's design. unit and two tape transports for convenient mass-memory storage. DECtape is Digital's com­ Hardware includes 4,096 18-bit words of core pact, inexpensive answer to the problems of memory and a Model ASR33 Teletype console program and data storage. A single pocket-sized teleprinter. The system has the rapid PDP-IS reel of tape can accommodate up to ISO,OOO 800-ns memory cycle time which provides 1.6-Ms words of information. The extra-heavy duty add capability. Facilities for later expansion are K S R 3S Teletype unit is included in the prewired into the system; additional memory PDP-IS/20 configuration to guarantee a high and peripherals can be plugged in as they are degree of reliability under the strain of con­ required. tinued heavy use. Also included is the extended arithmetic element described in Chapter 3. This Software is governed by the COMPACT Pro­ unit facilitates high-speed multiplication, divi­ gramming System, a complete package including sion, shifting, normalization, and register mani­ Assembler, Editor, Octal Debugging Technique, pulation.