The BCL Molecular 18 was a range of 18-bit

18-bit

18 binary digits have unique combinations.-Example 18-bit computer architectures:* Possibly the most well-known 18-bit computer architectures are the PDP-1, PDP-4, PDP-7, PDP-9 and PDP-15 minicomputers produced by Digital Equipment Corporation from 1960 to 1975.* UNIVAC produced a number of...

 computers

Computer

A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...

 originally manufactured by Systemation Limited and serviced by Business Mechanisation Limited. The two companies merged in 1968 to form Business Computers Limited - a public limited company. Business Computers Ltd subsequently went into receivership in 1974. By 1976, Business Computers (Systems) Ltd had been formed and were selling the Molecular. BC(S) Ltd subsequently went public in 1981 to form Business Computers (Systems) Plc.

Model	Released	Usage	Features	Storage
Betsie/Dottie	Unknown	Used for calculating odds for bookmakers
SADIE	1966	Sales And Daily Invoicing Electronically	Programming stored on soldered-through connectors on double-sided printed circuit cards, connecting instruction type on one side of the card with instruction number on the other side. IBM 2741 IBM 2741 The IBM 2741 was a printing computer terminal introduced in 1965.It combined a ruggedized Selectric typewriter mechanism with IBM SLT electronics and an RS-232-C serial interface. It operated at about 14.1 characters per second with a data rate of 134.5 bits/second...  Selectric-style golf-ball teleprinter for user interface.	Nickel acoustic delay line working storage (8 words of decimal arithmetic). Paper tape and edge-punched cards. Magnetic stripe cards for the teleprinter-style user interface.
SUSIE	1967	Stock Updating and Sales Invoicing Electronically	Programmes (2) stored on drum, each with 1000 machine instructions. Programme could be loaded from or written out to paper tape. User interface as SADIE.	As for SADIE, plus magnetic drum (6k words)
Mark 1	1970 Ferrite core memory.	Front-loading disk drive Disk storage Disk storage or disc storage is a general category of storage mechanisms, in which data are digitally recorded by various electronic, magnetic, optical, or mechanical methods on a surface layer deposited of one or more planar, round and rotating disks...   Optional paper tape reader Punched tape Punched tape or paper tape is an obsolete form of data storage, consisting of a long strip of paper in which holes are punched to store data...	-	Mark 2	1973 DD1600 CDC top-loading disk drives one fixed one removable and/or a large multi-platter CDC removable disk drive.		Water-cooled and fence registers
Mark 3
Mark 4		SOP, Livestock Markets	Core Memory or static RAM	CDC Hawk disk drives up to 4 supported per controller, max 2 controllers and/or a large multi platter CDC removable disk drive.	Mark 5	1984	SOP, Livestock Markets	New design of processor cards. Initially large-format ferrite core memory later static RAM. Bank switching memory. Support for CDC Lark disk drives	Up to four CDC Lark or Amcodyne drives per controller, max 2 controllers. Designed and produced by Systemation Developments for Business computers Systems.
Distributor	1986	SOP, Livestock Markets	Smaller version of the Mark 5 with a CDC Lark drive built in	Support for seven additional external Lark or Amcodyne drives 4 per controller including the integral drive. Designed and produced by Systemation Developments for Business computers Systems.
Distributor EP	1989	SOP, Livestock Markets	Enhanced version of the Distributor	SCSI disk and tape support

Note that neither SADIE nor SUSIE shared any technology with the Molecular series.

External links

• BCL Molecular
• BCL Molecular 18 Minicomputer
• BCL Susie Computer @ The Centre for Computing History