Ferranti Mark I
Encyclopedia
The Ferranti Mark 1, also known as the Manchester Electronic Computer in its sales literature, and thus sometimes called the Manchester Ferranti, was the world's first commercially available general-purpose electronic
computer. It was "the tidied
up and commercialised version of the Manchester computer".
which was delivered to the United States Census Bureau
a month later.
The machine was built by Ferranti
of the United Kingdom. It was based on the Manchester Mark 1
, which was designed at the University of Manchester
by Freddie Williams
and Tom Kilburn
. The Manchester Mark 1 effectively served as a prototype for the Ferranti Mark 1; the main improvements over it were in the size of the primary and secondary storage, a faster multiplier, and additional instructions.
The Mark 1 used a 20-bit word stored as a single line of dots on a Williams tube
display, each tube storing 64 "lines" of dots. Instructions were stored in a single word, while numbers were stored in two words. The main memory consisted of eight tubes, each storing one such "page" of 64 words. Other tubes stored the single 80-bit accumulator
(A), the 40-bit "multiplicand/quotient register" (MQ) and eight "B-lines", or index register
s, which was one of the unique features of the Mark 1 design. The accumulator could also be addressed as two 40-bit words. An extra 20-bit word per tube stored an offset value into the secondary storage. Secondary storage was provided in the form of a 512-page magnetic drum, storing two pages per track, with about 30 milliseconds revolution time. The drum provided eight times the storage of the original designed at Manchester.
The instructions, like the Manchester machine, used a "single address" format in which operands were modified and left in the accumulator. There were about fifty instructions in total. The basic cycle time was 1.2 milliseconds, and a multiplication could be completed in the new parallel unit in about 2.16 milliseconds (about five times faster than the original). The multiplier used almost a quarter of the machine's 4,050 vacuum tube
s. Several instructions were included to copy a word of memory from one of the Williams tubes to a paper tape machine, or read them back in. Several new instructions were added to the original Manchester design, including a random number
instruction and several new instructions using the B-lines.
The original Mark 1 had to be programmed by entering alphanumeric characters representing a 5-bit value that could be represented on the paper tape input. The engineers decided to use the simplest mapping between the paper holes and the binary digits they represented, but the mapping between the holes and the physical keyboard was never meant to be a binary mapping. As a result the characters representing the values from 0–31 (5-bit numbers) looked entirely random, specifically /E@A:SIU½DRJNFCKTZLWHYPQOBG"MXV£. Each instruction was represented by a single character.
The first machine was delivered to the University of Manchester. Ferranti had high hopes for further sales, and were encouraged by an order placed by the Atomic Energy Research Establishment
for delivery in autumn 1952. But a change of government while the machine was being built led to all government contracts over ₤100,000 being cancelled, leaving Ferranti with a partially completed Mark 1. The machine, nicknamed FERUT, was eventually purchased by the University of Toronto
at "fire sale" prices, and was extensively used in business, engineering, and academia.
for better usability. Instead of the original mapping from holes to binary digits that resulted in the random-looking mapping, the new machines mapped digits to holes in order to produce a much simpler mapping, ø£½0@:$ABCDEFGHIJKLMNOPQRSTUVWXYZ. Additionally several commands that used the index registers had side-effects that led to quirky programming, but these were modified to have no side-effects. Similarly, the original machines' JUMP instructions landed at a location "one before" the actual address, for reasons similar to the odd index behavior, but these proved useful only in theory and quite annoying in practice, and were similarly modified. Input/output was also modified, with 5-bit numbers being output least significant digit to the right, as is typical for most numeric writing. These, among other changes, greatly improved the ease of programming the newer machines. At least seven of the Mark 1* machines were delivered between 1951 and 1957, one of them to Shell
labs in Amsterdam
.
Tim Berners-Lee
's parents both worked on the Ferranti Mark 1 and Mark 1*.
". The recording was made by the BBC
towards the end of 1951, and the programming was done by Christopher Strachey
, a maths teacher at Harrow
and a friend of Alan Turing
. It was not however the first computer to have played music – CSIRAC
, Australia's first digital computer, achieved that with a rendition of Colonel Bogey.
; no double move, no en passant
, and no promotion for pawns; no distinction between checkmate
and stalemate
.
Electronics
Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...
computer. It was "the tidied
up and commercialised version of the Manchester computer".
History and specifications
The first machine was delivered to the University of Manchester in February 1951, just ahead of the UNIVAC IUNIVAC I
The UNIVAC I was the first commercial computer produced in the United States. It was designed principally by J. Presper Eckert and John Mauchly, the inventors of the ENIAC...
which was delivered to the United States Census Bureau
United States Census Bureau
The United States Census Bureau is the government agency that is responsible for the United States Census. It also gathers other national demographic and economic data...
a month later.
The machine was built by Ferranti
Ferranti
Ferranti or Ferranti International plc was a UK electrical engineering and equipment firm that operated for over a century from 1885 until it went bankrupt in 1993. Known primarily for defence electronics, the Company was once a constituent of the FTSE 100 Index but ceased trading in 1993.The...
of the United Kingdom. It was based on the Manchester Mark 1
Manchester Mark 1
The Manchester Mark 1 was one of the earliest stored-program computers, developed at the Victoria University of Manchester from the Small-Scale Experimental Machine or "Baby" . It was also called the Manchester Automatic Digital Machine, or MADM...
, which was designed at the University of Manchester
Victoria University of Manchester
The Victoria University of Manchester was a university in Manchester, England. On 1 October 2004 it merged with the University of Manchester Institute of Science and Technology to form a new entity, "The University of Manchester".-1851 - 1951:The University was founded in 1851 as Owens College,...
by Freddie Williams
Frederic Calland Williams
Sir Frederic Calland Williams CBE, FRS , known as 'Freddie Williams', was an English engineer....
and Tom Kilburn
Tom Kilburn
Tom Kilburn CBE, FRS was an English engineer. With Freddie Williams he worked on the Williams Tube and the world's first stored-program computer, the Small-Scale Experimental Machine , while working at the University of Manchester.-Computer engineering:Kilburn was born in Dewsbury, Yorkshire and...
. The Manchester Mark 1 effectively served as a prototype for the Ferranti Mark 1; the main improvements over it were in the size of the primary and secondary storage, a faster multiplier, and additional instructions.
The Mark 1 used a 20-bit word stored as a single line of dots on a Williams tube
Williams tube
The Williams tube or the Williams-Kilburn tube , developed in about 1946 or 1947, was a cathode ray tube used to electronically store binary data....
display, each tube storing 64 "lines" of dots. Instructions were stored in a single word, while numbers were stored in two words. The main memory consisted of eight tubes, each storing one such "page" of 64 words. Other tubes stored the single 80-bit accumulator
Accumulator (computing)
In a computer's central processing unit , an accumulator is a register in which intermediate arithmetic and logic results are stored. Without a register like an accumulator, it would be necessary to write the result of each calculation to main memory, perhaps only to be read right back again for...
(A), the 40-bit "multiplicand/quotient register" (MQ) and eight "B-lines", or index register
Index register
An index registerCommonly known as a B-line in early British computers. in a computer's CPU is a processor register used for modifying operand addresses during the run of a program, typically for doing vector/array operations...
s, which was one of the unique features of the Mark 1 design. The accumulator could also be addressed as two 40-bit words. An extra 20-bit word per tube stored an offset value into the secondary storage. Secondary storage was provided in the form of a 512-page magnetic drum, storing two pages per track, with about 30 milliseconds revolution time. The drum provided eight times the storage of the original designed at Manchester.
The instructions, like the Manchester machine, used a "single address" format in which operands were modified and left in the accumulator. There were about fifty instructions in total. The basic cycle time was 1.2 milliseconds, and a multiplication could be completed in the new parallel unit in about 2.16 milliseconds (about five times faster than the original). The multiplier used almost a quarter of the machine's 4,050 vacuum tube
Vacuum tube
In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...
s. Several instructions were included to copy a word of memory from one of the Williams tubes to a paper tape machine, or read them back in. Several new instructions were added to the original Manchester design, including a random number
Random number
Random number may refer to:* A number generated for or part of a set exhibiting statistical randomness.* A random sequence obtained from a stochastic process.* An algorithmically random sequence in algorithmic information theory....
instruction and several new instructions using the B-lines.
The original Mark 1 had to be programmed by entering alphanumeric characters representing a 5-bit value that could be represented on the paper tape input. The engineers decided to use the simplest mapping between the paper holes and the binary digits they represented, but the mapping between the holes and the physical keyboard was never meant to be a binary mapping. As a result the characters representing the values from 0–31 (5-bit numbers) looked entirely random, specifically /E@A:SIU½DRJNFCKTZLWHYPQOBG"MXV£. Each instruction was represented by a single character.
The first machine was delivered to the University of Manchester. Ferranti had high hopes for further sales, and were encouraged by an order placed by the Atomic Energy Research Establishment
Atomic Energy Research Establishment
The Atomic Energy Research Establishment near Harwell, Oxfordshire, was the main centre for atomic energy research and development in the United Kingdom from the 1940s to the 1990s.-Founding:...
for delivery in autumn 1952. But a change of government while the machine was being built led to all government contracts over ₤100,000 being cancelled, leaving Ferranti with a partially completed Mark 1. The machine, nicknamed FERUT, was eventually purchased by the University of Toronto
University of Toronto
The University of Toronto is a public research university in Toronto, Ontario, Canada, situated on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution of higher learning in Upper Canada...
at "fire sale" prices, and was extensively used in business, engineering, and academia.
Mark 1 Star
After the first two machines a revised version of the design became available, known as the Ferranti Mark 1* or the Ferranti Mark 1 Star. The revisions mainly cleaned up the instruction setInstruction set
An instruction set, or instruction set architecture , is the part of the computer architecture related to programming, including the native data types, instructions, registers, addressing modes, memory architecture, interrupt and exception handling, and external I/O...
for better usability. Instead of the original mapping from holes to binary digits that resulted in the random-looking mapping, the new machines mapped digits to holes in order to produce a much simpler mapping, ø£½0@:$ABCDEFGHIJKLMNOPQRSTUVWXYZ. Additionally several commands that used the index registers had side-effects that led to quirky programming, but these were modified to have no side-effects. Similarly, the original machines' JUMP instructions landed at a location "one before" the actual address, for reasons similar to the odd index behavior, but these proved useful only in theory and quite annoying in practice, and were similarly modified. Input/output was also modified, with 5-bit numbers being output least significant digit to the right, as is typical for most numeric writing. These, among other changes, greatly improved the ease of programming the newer machines. At least seven of the Mark 1* machines were delivered between 1951 and 1957, one of them to Shell
Royal Dutch Shell
Royal Dutch Shell plc , commonly known as Shell, is a global oil and gas company headquartered in The Hague, Netherlands and with its registered office in London, United Kingdom. It is the fifth-largest company in the world according to a composite measure by Forbes magazine and one of the six...
labs in Amsterdam
Amsterdam
Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...
.
Tim Berners-Lee
Tim Berners-Lee
Sir Timothy John "Tim" Berners-Lee, , also known as "TimBL", is a British computer scientist, MIT professor and the inventor of the World Wide Web...
's parents both worked on the Ferranti Mark 1 and Mark 1*.
Oldest recorded computer music
Included in the Ferranti Mark 1's instruction set was a hoot command, which enabled the machine to give auditory feedback to its operators. The sound generated could be altered in pitch, a feature which was exploited when the Mark 1 made the earliest known recording of computer music, playing a medley which included "God Save the King", "Baa Baa Black Sheep", and "In the MoodIn the Mood
"In the Mood" is a big band era #1 hit recorded by American bandleader Glenn Miller. Joe Garland and Andy Razaf arranged "In the Mood" in 1937-1939 using a previously existing main theme composed by Glenn Miller before the start of the 1930s...
". The recording was made by the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
towards the end of 1951, and the programming was done by Christopher Strachey
Christopher Strachey
Christopher Strachey was a British computer scientist. He was one of the founders of denotational semantics, and a pioneer in programming language design...
, a maths teacher at Harrow
Harrow School
Harrow School, commonly known simply as "Harrow", is an English independent school for boys situated in the town of Harrow, in north-west London.. The school is of worldwide renown. There is some evidence that there has been a school on the site since 1243 but the Harrow School we know today was...
and a friend of Alan Turing
Alan Turing
Alan Mathison Turing, OBE, FRS , was an English mathematician, logician, cryptanalyst, and computer scientist. He was highly influential in the development of computer science, providing a formalisation of the concepts of "algorithm" and "computation" with the Turing machine, which played a...
. It was not however the first computer to have played music – CSIRAC
CSIRAC
CSIRAC , originally known as CSIR Mk 1, was Australia's first digital computer, and the fourth stored program computer in the world. It was first to play digital music and is one of only a few surviving first-generation computers .The CSIRAC was constructed by a team led by Trevor Pearcey and...
, Australia's first digital computer, achieved that with a rendition of Colonel Bogey.
One of oldest computer games
In November 1951, Dr. Dietrich Prinz wrote one of the oldest computer games, a chess-playing program for the Manchester Ferranti Mark 1 computer. The limitation of the Mark 1 computer did not allow for a whole game of chess to be programmed. Prinz could only program mate-in-two chess problems. The program would examine every possible move for White and Black (thousands of possible moves) until a solution was found. This took an average of 15 to 20 minutes to do so. The program’s restrictions were: no castlingCastling
Castling is a special move in the game of chess involving the king and either of the original rooks of the same color. It is the only move in chess in which a player moves two pieces at the same time. Castling consists of moving the king two squares towards a rook on the player's first rank, then...
; no double move, no en passant
En passant
En passant is a move in the board game of chess . It is a special pawn capture which can occur immediately after a player moves a pawn two squares forward from its starting position, and an enemy pawn could have captured it had it moved only one square forward...
, and no promotion for pawns; no distinction between checkmate
Checkmate
Checkmate is a situation in chess in which one player's king is threatened with capture and there is no way to meet that threat. Or, simply put, the king is under direct attack and cannot avoid being captured...
and stalemate
Stalemate
Stalemate is a situation in chess where the player whose turn it is to move is not in check but has no legal moves. A stalemate ends the game in a draw. Stalemate is covered in the rules of chess....
.