DCJ11 Microprocessor User's Guide

This is a preliminary User's Guide (October 1983) for the Digital Equipment Corporation (DEC) DCJ11 microprocessor CPU chip. Its main purpose is to familiarize readers with the hardware and software characteristics of the DCJ11, assuming prior experience with microprocessor design and PDP-11 architecture.

The guide is organized into chapters and appendices, covering:

• Architectural Overview: Introduces the DCJ11's general architecture, including general-purpose registers, the Processor Status Word, interrupts, traps, the CPU error register, stack protection, floating-point processing, memory system registers, and direct memory access (DMA).
• Pin Description: Details the function of each DCJ11 pin, categorizing them into data/address lines, system control lines, timing signals, start/stop control, status signals, interrupt/DMA control, oscillator pins, and power pins.
• Bus Cycles: Describes various types of DCJ11 bus cycles (e.g., Non-I/O, Bus Read/Write, General-Purpose Read/Write, Interrupt Acknowledge) and their timing relationships.
• Memory Management: Explains the architecture and operation of the DCJ11's integral Memory Management Unit (MMU), covering addressing, I/D space, management registers (PARs, PDRs, MMRs), fault recovery, MMU implementation details, and memory page configurations.
• Special Features: Highlights key features such as cache memory status and control registers, the console ODT (Octal Debugging Technique) for interactive debugging, and the microprocessor's pipeline processing mechanisms.
• Instruction Sets: Provides comprehensive descriptions of the DCJ11's base instruction set (addressing modes, single-operand, double-operand, logical, program control, and miscellaneous instructions) and the integral floating-point arithmetic unit with its dedicated instruction set, including data formats and accuracy considerations.
• Interfacing: Offers introductory information on interfacing external logic to the DCJ11, including power-up and initialization circuits.

Appendices provide supplementary technical data:

• DC and AC Electrical Characteristics: Summaries of the microprocessor's electrical specifications.
• Hardware and Software Differences: Compares the DCJ11 with other PDP-11 processors (PDP-11/44 and PDP-11/70) in terms of hardware and software features.
• Instruction Timing: Guidelines for determining the duration of DCJ11 instructions for both base and floating-point instruction sets.
• Glossary: Definitions of common DCJ11 terms.

As a preliminary document from 1983, the material is stated to be for informational purposes and subject to change without notice.