DECUS 12 BIT SPECIAL INTEREST GROUP NEWSLETTER Number 30 September 1978

This September 1978 issue of the DECUS 12 Bit Special Interest Group Newsletter provides comprehensive updates on software, hardware, and community activities relevant to PDP-8 and PDP-12 users.

Key Announcements:

• DECUS Headquarters Relocation: Effective August 14, 1978, DECUS International Headquarters and the U.S. Chapter moved to One Iron Way, Marlboro, MA, with new contact details and extensions provided.

Symposium Information:

• The Fall DECUS/US Symposium agenda includes 16 hours of 12-Bit related sessions, covering topics such as 12-Bit SIG meetings, software workshops for DECSTATION 78/88, PDP-8 programming tools, RTS-8, OS/8 papers, and a TECO Tutorial.
• The Fall-78 MICRO-8 symposium program is detailed, featuring application papers on systems like the DECstation-78, an Ocean Based Seismometer System, GDP-12 Geophysical Data Acquisition System, MICRO-8 Development System, and a PDP-8 Development System for Bit Slice Microprocessors, complemented by a Hardware/Software Workshop.
• A summary of the Spring-78 Symposium highlights the introduction of Commercial Basic and Symbiont features for the DECstation-78 and limited 128k word support in upcoming OS/8 releases.

Software Updates & Enhancements (OS/78 V2):

• The OS/78 Version 2 update kit introduces numerous features, including enhanced VT-52 terminal support, full 7-bit ASCII (upper/lower case) handling in BASIC, new RS (Run with free space report) and EDIT commands (search/replace strings, copy lines), automatic line numbering (SEQUENCE), code combining (WEAVE), improved numeric input, ON-GOTO/ON-GOSUB statements, IF OPEN # for file success checks, PRINT USING for formatted output, TAN/ATN functions, CAP$ for case conversion, CCL command for program exit to command line, and octal conversion functions (OCT, OCS$).
• The "Multifunction Operation" (Symbiont) feature allows concurrent tasks (e.g., a print spooler) on DECstation-78 systems, with specific programming requirements and limitations.
• CCL commands now support multicharacter switches (e.g., DIR /BRIEF) for improved DCL compatibility, though the source code for CCL is not available for user extension.

User Contributions & Discussions:

• PDP-8/12 & OS/8 Topics: Contributions include methods for transferring ADVENTURE source files from RT-11 to OS/8, enhancements to DECsystem 8 CCL, and requests for Z-80/8080/6800 cross-assemblers capable of running on PDP-8/12 systems.
• Hardware Modifications: Detailed instructions with circuit diagrams are provided for adding write protection to RX01 floppy disk drives. A modification for Straight-8 CPUs is also presented to resolve issues with combining INC and ROTATE instructions.
• FPP-12 Fixed-Point Calculations: An in-depth article explores the challenges and techniques for performing fixed-point arithmetic on the FPP-12, including conversions between precision types and fixed/floating point, and an analysis of a test program demonstrating precision issues.

• Software Performance Reports (SPRs): Several SPRs highlight reported bugs and proposed fixes for OS/8 V3D components:

  • EDIT V12B: Describes issues with the N command handler affecting output buffering.
  • PIP V11A: Details a "BAD SYSTEM HEAD" error when input files are on non-system devices and a critical bug in the /Y code causing device handler overlays.
  • CCL.PA V3D: Addresses unpredictable results and system crashes when using @file.CM with semicolons due to buffer conflicts with keyboard monitor routines.
  • BASIC.FF V3D: Reports invalid "FE" errors and system crashes during file operations (OPEN/CLOSE), attributed to driver space de-allocation not being properly communicated to the USR, and issues with opening file #0.

• Other Technical Notes: The newsletter includes discussions on a DECUS program 8-690 (RANDU random number generator) malfunctioning under OS/8 FORTRAN IV with the Extended Arithmetic Element (EAE) enabled, proposed patches for OS8BOL and OS8PAL regarding date handling, and a "self erasing core zeroer" technique for memory.

• International Perspective: Information is shared about a European 6100 microprocessor-based Micro-Computer system, outlining its 32k word memory and available interface cards.
• Documentation: A list of updated PDP-8 and OS/8 related manuals, including order numbers, is provided for users interested in evaluating new features.
• MULTOS-8 Project: A note from Bill Haygood announces the completion and availability of MULTOS-8 (Multi-user OS/8), detailing its supported hardware, multi-user capabilities, print spooling, batch processing, and other features.