UBC installed the ALWAC III-E, invented by Axel Wenner-Gren, for the then-price of $80,000. It was in operation until 1961, and was replaced by an IBM 1620.

Excerpt from BRL Report - 1961;

Construction (Arithmetic unit only):

Vacuum-tubes: 132

Diodes: 5,000

Arithmetic mode: Serial

Timing: Synchronous

Operation: Sequential

Two commands at once are picked off the drum and unless the first command of the pair is an executed jump instruction, a second access to the drum is not required. as the next command is held ready for immediate use in a static register.

PROGRAMMING AND NUMERICAL SYSTEM

Internal number system: Binary

Binary digits per word: 32 + sign Binary

Digits/instruction: 16

Instructions per word: 2, 3 or 4

Instructions decoded: 101 Basic (Many are micro programmable)

Arithmetic system: Fixed point. Commands normally consider numbers to be integral

Instruction type: One address. Optimum sequencing is built in

Number range: 64 bits

Negative numbers are indicated by sign. Decimal input and output are built-in with a single command capable of taking in up to 8 digits. Several systems are available both for floating point or fined point operations. Neumonic interpretive routines as well as symbolic compilers are in use. There are four registers, viz, a main accumulator 32 bits + sign + recoverable overflow bit, a secondaryaccumulator 32 bits + sign, an auxiliary register 32 bits + sign, and a 16 bit B-Box Index register. The first two registers are combined for double precision operations. Also, complete shiftabilityapplies to main accumulator as Knell as double length accumulator. Auxiliary register is used in multiplication, division, for special floating point assistance commands and risking operations.

ARITHMETIC UNIT

Incl Stor Access Exclud. Stor Access

Microsec Microsec

Add 1,000 1,000

Mult 17,000 17,000

Div 17,000 17,000

# ALWAC III-E

Tuesday, January 1, 1957 to Sunday, January 1, 1961