9db6ca5147
1. Implement new single-precision add/subtract routine that more closely follows the real B5500 logic. 2. Implement tests/B5500SPMathTest.html testbed to exercise the new add/subtract implementation. 3. Implement new way to focus the ConsolePanel window after the SPO becomes ready during initialization. 4. Add "?db=" parameter to tools/B5500DeleteStorageDB.html to specify the disk storage data base name. 5. Implement "Execute Single" button in B5500SyllableDebugger to preserve the T register when testing a single syllable. 6. Implement "octize" and "pic*" function in B5500Util to support tests/B5500SPMathTest.html. 7. Commit minor changes to webSite index page and GitHub README.md. Commit version 1.03b: 1. Remove initial window open/close (to destroy any existing windows) from Console, I/O device classes, and configuration utilities. 2. Commit Mark XV MESAGE/CANDE file for reconstructed SYSTEM tape, donated by Rich Cornwell. Commit version 1.03a: 1. Correct character translation for even-parity tape operations. 2. Implement normal tape space operation for tape maintenance space operation (temporary solution to fix problem with Mark XV tape parity recovery -- Mark XIII did not issue maintenance space I/Os). 3. Modify B5500MagTapeDrive to report EOF+parity when attempting to ready beyond the end of the internal tape image (previously reported only parity error). 4. Restate B5500Processor delay deviation and processor slack time average calculations and increase the alpha for the running exponential averages to smooth out the reporting on the B5500ConsolePanel. 5. Improve delay timing calculation for B5500CardPunch, B5500CardReader. and B5500LinePrinter.
The Burroughs B5500 was an innovative computer system. Released first as the B5000 in 1962 and then, with minor improvements and a new disk subsystem, re-released as the B5500 in 1964, its design was a radical departure from other commercial systems of the day. Many of the concepts that it embodied were being worked on and implemented by others around the same time, but it is difficult to think of another system that pulled so many new concepts together and made them work so well in a commercially-successful product:
- Stack- and descriptor-oriented instruction set
- Variable-length memory segments
- Hardware bounds checking
- Unified integer/floating-point numeric format
- Designed for and programmed exclusively in higher-level languages
- Designed for and managed by a sophisticated operating system, the Master Control Program, or MCP
- Multi-programming (multiple tasks sharing the same processor)
- Multi-processing (multiple physical processors sharing common memory and I/O)
- Automatic memory allocation and address relocation
- Automatic memory segment overlay (what we now call virtual memory)
- Use of labeled file media and automatic assignment of labeled file media to requesting programs (what we now call automatic volume recognition)
The B5500 was the foundation for the Burroughs B6000/7000/A Series, which are still produced and sold today as Unisys ClearPath MCP systems.
The main goal of this project is creation of a web browser-based emulator for the B5500. A second goal is reconstruction of the source and object code for the system.
A complete software release (Mark XIII, 1971) is presently available from the hosting site below under liberal terms of a Unisys educational/hobbyist license.
The contents of this project are licensed under the MIT License.
| Related Sites | URL |
|---|---|
| Getting Started | http://www.phkimpel.us/B5500/webSite/HelpMenu.html |
| Project Blog | http://retro-b5500.blogspot.com/ |
| Web/email Forum | http://groups.google.com/group/retro-b5500 |
| Emulator hosting site | http://www.phkimpel.us/B5500/ |
| Burroughs Mark XIII Software Release | http://www.phkimpel.us/B5500/webSite/SoftwareRequest.html |
| B5500 at retroComputingTasmania | http://www.retrocomputingtasmania.com/home/projects/burroughs-b5500 |
| Documents at bitsavers.org | http://bitsavers.org/pdf/burroughs/B5000_5500_5700/ |
| Release Downloads | https://drive.google.com/folderview?id=0BxqKm7v4xBswM29qUkxPTkVfYzg&usp=sharing |
This project was originally hosted on Google Code at https://code.google.com/p/retro-b5500 and moved to GitHub in June 2015.