Multi8

This document details the features and system improvements introduced in version V7A of the Multi8 operating system, specifically for users transitioning from version V6.

Key updates and changes include:

• Virtual Memory: The system now swaps only the necessary fields of a background program rather than the entire memory image. This enhances CPU throughput, reduces response times, and allows for flexible background sizes ranging from 8K to 32K.
• Terminal Support: Users can now define custom escape codes for different terminal types. Additionally, terminal buffering has been optimized using a shared pool of 16-word blocks, which halves memory requirements while allowing for smoother operation.
• Detached Terminals: A new mechanism allows running more background tasks than there are physical terminals. Users can "hook" their terminal to different background tasks as needed.
• Building Procedure: The system generation process has been simplified and automated, reducing the need to manually edit source files and allowing for easier task building.
• Reliability: Improvements include protection against spurious interrupts (via a reset/wait-loop mechanism) and dynamic memory detection at startup to handle hardware failures.
• Task Conversion: Version V7A introduces new protocols for task headers and emulator tasks, including changes to how tasks are entered in the emulator table (ASEMTB) and the introduction of a new "BREAK" mechanism to replace "KILL."
• Disk Configuration: The previous "virtual disk file" system has been replaced with a more flexible scheme that automatically initializes user disks, allowing for simpler disk allocation and the use of "public" disks for common file storage.