DEC LANcontroller 400 Technical Manual

This document is the "DEC LANcontroller 400 Technical Manual" (Order Number: EK-DEMNA-TM-001).

It describes the DEC LANcontroller 400, also known as the DEMNA controller, an Ethernet/802 controller designed for systems with an XMI bus to facilitate communication within a local area network.

The manual serves as a comprehensive technical reference for:

• Installation: How to physically install the DEMNA module.
• Troubleshooting & Repair: Diagnostic routines (ROM-based and software-based), error handling mechanisms, and procedures for identifying and resolving issues, including interpreting self-test results and error logs.
• Device Driver & Diagnostics Development: Detailed information on hardware functions, data structures (like the Port Data Block and rings), registers (XMI and port registers), and data flow to assist in writing or customizing software.

Key topics covered include:

• Module Overview: Basic functions, logical architecture (microprocessor, shared memory, Ethernet, XMI subsystems), and physical description.
• Port Operation: Shared data structures, port registers, commands, interrupts, port states, network maintenance operations (loopback, remote console, boot), packet filtering, and validation.
• Data Flow: Detailed descriptions of transmit and receive data paths.
• Power Management: Power-up, reset, and shutdown sequences.
• Console Monitor Program: Instructions on setting up, invoking, and using the console monitor for real-time monitoring of DEMNA operation, network traffic, and accessing diagnostic information.
• EEPROM Management: Procedures for updating firmware and modifying operational parameters stored in the EEPROM.

The manual is intended for Digital customer service representatives, self-maintenance customers, customer engineers, and system programmers who incorporate DEMNA modules into their products or systems.