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FreeBee -- AT&T UNIX PC emulator

I'm developing an emulator for the AT&T UNIX PC. Currently it can boot the 3B1 UNIX operating system and run acceptably.

There are some documents and other items here which may be useful to 3B1 owners.

The emulator currently boots 3B1 UNIX, and thanks to the hard efforts of many people, can run a wide variety of software (including, thanks to Jesse, the C compiler and MGR windowing system!).

The serial ports, printer port and modem are not currently emulated. I'm currently looking for a good way to create a “virtual” serial port device on Linux, Windows and Mac OS X.

Downloads

The source code is hosted on Github: https://github.com/philpem/freebee

You will need the Boot ROMs to use this.

To install, build the code as per the README. You will need to compile the emulator, create a hard drive image, then follow the instructions in the AT&T manuals (on www.bitsavers.org/pdf/att/3b1) to install the System Software (in Imagedisk format at http://www.bitsavers.org/bits/ATT/unixPC/).

You will need to use Imagedisk's “IMDU” utility to convert the IMD images into binary disk image files before using them with FreeBee.

Thanks and Acknowledgements

The 3B1 emulator would not be possible without the generous donation of two AT&T UNIX PC systems and software disks by Antoni Sawicki.

Andrew Warkentin has contributed many significant patches which improve the quality of the emulation and allow UNIX to be booted inside the emulator.

Jesse Booth put in a lot of time debugging and fixing the long-standing “PAGEIN” bug which prevented the C compiler from being used. Jesse also added support for the VIDPAL video PAL, and ImageDisk disk format support.

ROMs

Boot ROMs.

This ZIP file contains binary and Intel Hex images of the two 3B1 Boot ROMs.

These are fitted at board locations 14C and 15C, and carry part numbers 72-00616 and 72-00617 respectively.

Other software and documentation resources

Technical documentation

Steven Hirsch scanned the entire two-binder 3B1 UNIX PC Technical Reference and released them on the Classic Computers Mailing List. With his permission, his scans are mirrored here.

Reference Manual

Circuit diagrams and schematics

Peripherals

System bus specification