It adopted the then high 1 megahertz clock rate of the Pilot ACE.

(The DEUCE at the University of New South Wales {UTECOM} had a Siemens M100 teleprinter attached in 1964, giving 10 characters per second input/output).

Compared with contemporaries such as the Manchester Mark 1, DEUCE was about ten times faster.

In the early machines, all instructions involving the magnetic drum were interlocked while an operation was in progress.

From about 1958, seven extra delay lines could be attached, giving 224 more words of high-speed store.

An IBM 528 combined reader–punch could be substituted for the Hollerith equipment, giving the same input/output speeds, in which case the machine was called Mark II.

Automatic conversion of alphanumeric data to BCD was provided on input, and the reverse operation on output, for all eighty card columns.

The principal high-level programming languages were GEORGE (General Order Generator),[4][5][6][7] ALPHACODE, STEVE, TIP, GIP,[8] and ALGOL.

[10] Invented by Charles Leonard Hamblin in 1957, GEORGE was closest to present-day programming languages.

Its principal service was in the running of programs from the several hundred in the DEUCE linear algebra library.

[11] A short program to read in a matrix from cards, to transpose the matrix, and to punch the results on cards requires the following codewords: In each of the codewords, the fourth number is the brick number.

For operations on the single registers, the earliest time that the next instruction could be obeyed was 64 microseconds after the present one.

Optimum programming meant that as each instruction was executed, the next one was just emerging from a Delay Line.

The instruction store consisted of twelve mercury delay lines, each of 32 words, and numbered 1 to 12.

Delay line 11 (DL11) served as the buffer between the magnetic drum and the high-speed store.

Thus, for example, 32 words read from the drum could be transferred as a block to any of the other delay lines; four words could be transferred as a block from one quadruple register to the other, or between a quadruple register and a delay line—all with one instruction.

The 32 words of a delay line could be summed by passing them to the single-length adder (by means of a single instruction).

The first three machines were delivered in the spring of 1955; in late 1958 a DEUCE Mark II improved model appeared.

The combined IBM 528 reader and punch behaved like the separate Hollerith units on the earlier DEUCE Mark I machines; however, it was also provided with hardware conversion of alphanumeric data to BCD on input, and vice versa on output.

The DEUCE Mark IIA provided seven extra mercury delay lines, each of 32 words.

A total of 33 DEUCE machines were sold between 1955 and 1964, two being purchased by the engine manufacturer Bristol Siddeley.