AA11-K 4-channel D/A and Display Control User's Manual

This document is the "AA11-K 4-channel D/A and display control user's manual" for the PDP-11 computer system. It describes a module featuring four independently buffered 12-bit Digital-to-Analog Converters (DACs) and associated display control logic.

The primary purpose of the AA11-K is to generate graphical output, specifically a 4096 x 4096 dot array, on various display units. It is designed for use with the VR17 CRT Display Monitor, but is also compatible with Tektronix 602, 604, 611, and 613 oscilloscopes, as well as X/Y and strip chart recorders.

Key features and functionalities include:

• Four 12-bit DACs: Provide bipolar output ranges that are jumper-selectable to ±5V, ±10V, or ±0.5V.
• Display Control: Allows users to intensify points (Z-pulse), control erase cycles for storage oscilloscopes, and enable write-through or non-store functions.
• Programming: Operations are controlled by loading data into the Display Status Register and D/A Buffer Registers.
• Modes and Delays: Offers four program-controlled modes for intensifying points and configurable delays (20µs, 80µs, 3µs for fast intensify, or externally determined) for X-Y amplifier settling.
• User Flexibility: Jumpers allow selection of intensification pulse polarity, magnitude, and duration.
• Interrupts: The module can generate interrupts upon completion of display intensification or erase operations.
• Interfacing: It interfaces directly to the PDP-11 Unibus and provides various TTL-compatible logic signals. The manual details electrical characteristics, cabling requirements, operational setup (including address, vector, and analog output range selection), and specific interfacing instructions for different oscilloscope models.
• Maintenance: Includes procedures for testing and calibrating the module's offset and gain.