3B1

3B1 / PC7300 / Unix PC

AT&T 3b1 Unix PC
Manufacturer	Convergent Technologies
Release date	1985 (1985)
Media	5¼-inch floppy disks, casette tapes
Operating system	AT&T Unix v3.51
CPU	Motorola MC68010 with custom Memory management unit clocked at 10Mhz
Storage capacity	Optional 10MB, 20MB, 40MB and 67MB hard drives
Memory	512KB to 4MB RAM
Display	348×720 pixel resolution
Input	Keyboard, 3-button Mouse

The 3B1 (also known as the PC7300, or Unix PC) was a Unix workstation computer originally developed by Convergent Technologies (later acquired by Unisys), and marketed by AT&T in the mid- to late-1980s. Despite the name, the 3B1 had little in common with AT&T's other 3B-series computers.

Hardware configuration

• 10 MHz Motorola MC68010 (16 bit external bus, 32 bit internal) with custom MMU
• Internal MFM hard drive, originally 5 MB, later models with up to 67 MB
• At least 512K RAM on main board, expandable via expansion cards
• 3 expansion slots
• Monochrome green phosphor 10-inch (250 mm) monitor
• Internal 300/1200 bit/s modem

PC7300

The initial PC700 model offered a very limited 512 KB of memory and an extremely slow 5 MB hard drive. This model, although progressive in offering a Unix system for desktop office operation, was painfully slow and had an aggravating 'grinding' noise even when not in active use. The modern-looking "wedge"design was innovative, and in fact the machine gained notoriety appearing in many movies as the token "computer".^{[citation needed]}

AT&T 3B1

A later enhanced model was renamed "3B1". The cover was redesigned to accommodate a full-height 67 MB hard drive. This cover change added a 'hump' to the case, expanded onboard memory to 1 or 2 MB, as well as added a better power supply.

Operating system

The operating system is based on UNIX System V Release 2, with extensions from 4.1 and 4.2BSD, System V Release 3 and Convergent Technologies. The last release was 3.51.

• 

  Picture of a running AT&T PC7300 showing the output of a simple C source file.

• Video of an AT&T PC7300 booting.

Programming languages

• SMC BASIC
• RM COBOL
• RM FORTRAN
• LPI FORTRAN
• LPI Pascal (programming language)
• LPI C (programming language)
• SVS FORTRAN
• SVS Pascal
• AT&T BASIC
• GNU C++
• LISP

Application software

• SMART System (Office Suite)
• Informix (DBM)
• Oracle (DBM)
• Multiplan (Spreadsheet)

Word processors

• Microsoft Word
• AT&T Word Processor
• Crystalwriter
• WordStar 2000
• Samna Word
• WordMarc
• SMART Word Processor

Games

• Pacman
• NetHack
• Chess
• Klondike ^[1]
• Life
• Mahjongg ^[2]
• Moria
• Robots
• Rocks
• Rogue
• Tetris

Utility

• HoneyDanBer UUCP package.
• Various Shells: Bourne, C, and Korn
• EMACS
• Kermit
• TeX
• SPICE/NUTMEG (circuit simulation tool)^[3]

The Store

The Store is a public domain software repository which was available for all 3B1 users.^[4]

Expansion Cards

• DOS-73 8086 co-processor card running MS-DOS, which could be fitted with an 8087 math co-processor chip. This board was designed and built for AT&T by Alloy Computer Products of Framingham MA.
• RAM card could be added using 1 or 2 MB RAM cards (up to a maximum of 4 MB)
• EIA/RAM combo cards contained extra RAM and two RS-232 serial ports.
• Dual EIA port card
• StarLAN 1Mbps LAN card
• Ethernet 10 Mbps LAN card
• VoicePower card allowed for the capture and digital recording of voice conversations.
• Tape drive card provided interface for 23 MB MFM Tape Cartridge Drive.
• Expansion chassis card was hard-wired to Expansion Chassis (with five added slots)

Networking

• StarLAN - 1 MB/s local area network typically used in star format.

See also

• 3B Computers

External links

• comp.sys.3b1 FAQ
• AT&T 3B1/7300 (UNIX PC) Information
• AT&T UNIX PC at old-computers.com

References

1. ^ http://unixpc.taronga.com/games/
2. ^ http://unixpc.taronga.com/comp.sources.3b1/volume01/
3. ^ http://unixpc.taronga.com/misc/
4. ^ http://unixpc.taronga.com/STORE/