Supporting "Smarter" Terminals
— William Schaub, Dale Sinder and Steve Zoppi 2025/05/09
Overview
Abstract
On CERL 1) NovaNET, support was added in the late 1980's for a “Smarter” PLATO 2) terminal that exceeded the capabilities of its predecessors 3).
With the advent of robust personal computers, the need to have special-purpose hardware was no longer necessary. Though prior generations of personal computer-based terminal emulators had been attempted, the limitations of the terminal platforms, displays and CPU characteristics limited what could be done in until displays could equal or surpass the capabilities of the PLATO terminal's 512×512 pixel density.
The ability to support other forms of rich graphics, native fonts, and more, led to the development of a significantly enhanced terminal software called PlatoAccess.
PlatoAccess was constructed to build upon the existing Level Zero ASCII Protocol and implemented the Level One ASCII Protocol .
As we continue to recover older lessons of historical import, we have come across lessons which use these features of PlatoAccess. Because CYBIS does not inherently (in Release 1), support these more advanced display capabilities. The Retro1 project has chosen to enhance CYBIS in Release 2, to implement these capabilities.
Accomplishing this is an on-going project. Enhancements build upon other accomplishments so this work must be conducted in phases. Each phase is documented here in the order in which they must be done. This work is conserved in the form of a TUTORIAL for the aspiring hobbyist.
Prioritization of Work
Work is prioritized as described above; by the natural programming need, with each feature providing a stepping stone to the next feature. Prioritization will then shift to doing the most likely to be encountered feature that is also very difficult to do without.
Prerequisites
- The most recent PlatoAccess PlatoAccess Terminal Emulator
- CDC.IO Version 3.1.0.2 or greater
- Retro1.org release of CYBIS Release 2
- unmodified versions of the following:
File Name File Type #Parts Account nmem tutor 6 s0nver nplato tutor 18 system ns0terms tutor 5 s0nver ns0notes tutor 9 s0nver plato tutor 18 system s0terms tutor 5 system s0notes tutor 9 system
- Understanding of
- PLATO File Operations
Overview of Activities
As noted above, this procedure assumes that you are using a CYBIS Release 2 system with no additional modifications applied to the following files:
nplato/plato(The “development, next version” of lessonplato)nmem/mem(The “development, next version ofmem)maintp(The production PLATO Maintenance Procedures shipped with CYBIS Release 2).ns0notes/s0notes(Part of the PLATO/CYBIS system library shipped with CYBIS Release 2).ns0terms/s0terms(Part of the PLATO/CYBIS system library shipped with CYBIS Release 2).
Failing to have a proper backup may lead to undesirable outcomes:
- You may accidentally overwrite work in progress on lessons
nplatoandnmem. - The replacement code file
plmodswill completely overwrite any modifications which may have been locally applied.
When completed, this procedure adds many new files and edits or replaces the contents of these key existing files:
ns0notes⇐ (New Copy)s0notes⇐ System Libraryos0notes⇐ (Old Copy)
ns0terms⇐ (New Copy)s0terms⇐ System Libraryos0terms⇐ (Old Copy)
maintsub⇐ Utility Jobsmaintp⇐ Build Procedures
nmem⇐ (New Copy)mem⇐ System Memory Vieweromem⇐ (Old Copy)
nplato⇐ (New Copy)plato⇐ System Lesson PLATOoplato⇐ (Old Copy)
nuser⇐ (New Copy)user⇐ System Lesson USERouser⇐ (Old Copy)
These procedures will also create a set of modifications which, when applied correctly, will implement features of the Level One PLATO Protocol.
It is highly recommended that you backup the entire system using the cdc.io backup subcommand.
The system lesson operator is used to promote the following files to “production” using the system standard procedure:
nplato→plato→oplatons0notes→s0notes→os0notesns0terms→s0terms→os0termsnmem→mem→omemnuser→user→ouser
You must successfully complete all steps in each phase before proceeding to the next.
Tutorial Phases
Tip
The tutorial phases are arranged in a prescribed order, wherein each phase builds upon the previous. Performing these activities out of order will leave the installation in an inconsistent, or perhaps inoperable state.