MIDAS

This document is a user's manual for the MIDAS (Multi Instrument Data Acquisition Software) and MSORT (MIDAS Sorter) programs, designed for the Digital Equipment Corporation's PDP-12 system.

MIDAS is a data acquisition program for the LDP system, capable of acquiring data from up to eight instruments synchronously or asynchronously, storing it on mass storage (RK8 Disk or LINCtape) at rates up to 15,000 Hertz. It supports various hardware configurations, including the AIP (Analytical Instrument Processor) and extended core. MIDAS enables experiment control via Schmitt Triggers, external syncs, analog inputs, clocks, sense lines, relays, and keyboard commands. Core keyboard commands include SETUP (for defining instrument parameters and creating a new run number), START, PAUSE, STOP, RESET, EXIT, RELAY, and TEST (for visual data display on the VR12 display). The instrument setup process guides users through defining run numbers, relay actions, START/PAUSE/STOP conditions (which can be keyboard, Schmitt trigger, or sense line controlled), data rates, and X;Y axes (instrument classification and AIP channel assignment). The manual also details "BURST MODE," an option for higher throughput at the cost of some features, and provides extensive Teletype messages for operational status and error reporting.

MSORT is a utility program designed to convert the raw data output from MIDAS into a standard AIPOS three-word floating point format, making it interpretable by other LDP software (e.g., DORA). It can process only MIDAS-generated files, allowing for the creation of up to eight output files or the execution of up to eight sorts in a single command. MSORT's keyboard commands include EXIT, ID (to display information about the logical MIDAS file), and SORT. The manual outlines MSORT's initialization (including an A/D converter query) and its handling of various data formats (12-bit/15-bit A/D, 18-bit binary, BCD to binary), along with its own set of Teletype messages for successful sorts, input/output errors, and file management issues.

Both MIDAS and MSORT require a PDP-12/40 and an AIP-12 Analytical Instrument Processor. MIDAS supports up to 24K of core, while MSORT supports up to 20K of core, with specific throughput rates tied to core size and storage device. The document includes appendices with user tips, operation summaries, typical lab connections, assembly instructions, and a glossary.