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Overview of the manual's content, covering description, installation, operation, programming, theory, and maintenance.
Details technical specifications of the LP20 controller, including registers, functions, and modes.
Explains the LP20 controller's functions, interface with the Unibus, and primary operations.
Describes the physical assemblies and modules comprising the LP20 Controller.
Lists related documentation for the LP20 Line Printer Systems.
Guide for installing LP20 controllers and line printers, focusing on detailed procedures.
Procedures for safely unpacking the line printer and the LP20 Controller from shipping containers.
Steps for inspecting all components after unpacking for any signs of damage.
Detailed procedures required for installing the LP20 Line Printer System.
Procedures to verify the AC power supply and system readiness.
Steps to perform a system checkout after installation to ensure proper operation.
Overview of LP20 programming, including operational modes and register descriptions.
Summarizes the four operational modes: RAM Load, DAVFU Load, Print Mode, and Test Mode.
Details the procedure for loading data into the system's RAM.
Explains loading the DAVFU for vertical format control and character storage.
Describes how the controller handles and prints characters, including error conditions.
Explanation of the diagnostic test mode for controller logic and operation.
Details controller registers, their bus addresses, and functions.
Information on the translation RAM and its use in character translation.
Description of the DAVFU's role in vertical format control and character data.
Procedure for initializing the LP20 controller locally.
Steps to reset and clear error conditions within the controller.
Overview of the data multiplexer and its associated components.
Detailed explanation of the CSRA register's bits and functions.
Detailed explanation of the CSRB register's bits and functions.
Description of the bus address register's function in address selection.
Explanation of the byte counter's operation in tracking data transfers.
Definition and use of escape sequences for character interpretation.
Handling of invalid characters during operation and their impact.
Detection and handling of memory parity errors.
Explanation of RAM parity generation and checking procedures.
A practical example demonstrating controller programming.
Introduction to the detailed theory of operation for the LP20 Controller.
General overview of the LP20 Controller's technical aspects.
Reference to logic diagrams for LP20 Controller modules.
In-depth explanation of the LP20 Controller's internal workings and signal paths.
Detailed explanation of each operational mode: Initialization, RAM Load, DAVFU Load, Print, Test.
How the system powers up and interacts with the controller.
Step-by-step process for initializing the controller.
How to access and modify controller registers via bus address and data lines.
Detailed behavior of the Non-Processor Request clock signal.
How the LP20 controller handles bus interrupts.
DMA transfer process for loading RAM.
Procedure for loading the DAVFU for vertical format control.
Comprehensive list and description of potential controller and printer errors.
Specific error condition: printer being off-line.
Handling of critical error types: GO Error, RAM Parity, Memory Parity.
Procedures for clearing detected errors from the controller.
Description of the LP05 line printer, including models, features, and performance.
Explanation of the interface signals used by the LP05 printer.
Summary of LP05 printer technical specifications, including power and environmental requirements.
Description of the LP07 line printer, including models, features, and performance.
Explanation of the interface signals used by the LP07 printer.
Summary of LP07 printer technical specifications, including power and environmental requirements.
Description of the LP10 line printer, including models, features, and performance.
Explanation of the interface signals used by the LP10 printer.
Summary of LP10 printer technical specifications, including power and environmental requirements.
Description of the LP14 line printer, including models, features, and performance.
Explanation of the interface signals used by the LP14 printer.
Summary of LP14 printer technical specifications, including power and environmental requirements.
Reference for ASCII characters and their corresponding 7-bit octal codes.
Mapping of 64 Data Processing (EDP) characters to their octal codes.
Mapping of 96 Data Processing (EDP) characters to their octal codes.
Chart mapping printer instructions and data bits to characters and functions.
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General