QMA DMV11 Synchronous Controller User's Guide

This user's guide for the QMA DMV11 Synchronous Controller provides comprehensive information for Field Service personnel on its installation, operation, and programming within distributed communication networks.

Key aspects of the document include:

• General Description: The DMV11 is a high-performance intelligent communications line controller designed for efficient, high-speed (up to 56K b/s) synchronous communication. It utilizes LSI-11 CPUs as control or tributary stations, leveraging DMA transfers to minimize main CPU resource usage. It supports both point-to-point and multipoint network configurations, operating in full-duplex or half-duplex modes, and offers various interfaces (RS-232-C, V.35, Integral Modem, RS-423-A/449).
• Networking Capabilities: It can manage up to 1 control station and 12 tributary stations in a multipoint setup, using a dynamic polling algorithm to optimize line utilization. Features include switch/program-selectable operating modes and tributary addresses, support for multiple-addressed tributaries, down-line loading, and remote load detection.
• System Operation & Interface: Communication between the user program and the DMV11 is handled via four 16-bit Control and Status Registers (CSRs), acting as a bidirectional port for commands and responses. Message data is transferred using nonprocessor requests (NPRs). The controller fully supports the Digital Data Communications Message Protocol (DDCMP), with its microcode handling all protocol processing.
• Command and Response Structures: The guide details various input commands (microprocessor control/maintenance, mode definition, control, buffer address/character count) and output responses (control, information, buffer disposition) that define the user-DMV11 interaction.
• Programming Techniques: It covers essential programming topics such as command/response discipline, DMV11 start-up procedures, specifying user-defined parameters (e.g., for polling algorithms via Tributary Status Slots (TSS) and Global Status Slot (GSS)), accessing error counters, and error recovery procedures. It also explains different methods for booting a remote station.
• Microcode Operation: The document delves into the internal workings of the DMV11's microcode, describing its polling algorithm (including urgency calculation and polling states), error recording mechanisms, and internal data structures like linked lists and status slots.
• Installation: Detailed instructions are provided for unpacking, pre-installation considerations (device placement, system requirements), physical installation of the module and cabling, and functional diagnostic testing.

In essence, the document serves as a comprehensive technical manual for understanding, installing, configuring, and troubleshooting the DMV11 Synchronous Controller for high-speed data communication in Digital Equipment Corporation's distributed networks.