Mercury Input Routine

The `input routine' read in alphanumeric machine code and translated it into binary form. It was in effect an assembler which used numeric codes rather than alphanumeric. The operation code numbers did not correspond to the binary op codes but were organised is a more easily remembered sequence. (See the Programmers' Manual.)

Using a mainly numeric assembly language was sensible given the inconvenience of the letter shift - figure shift requirements of the 5-bit input code.

The complete manual in .pdf form is here. The carefully hand written text is not always easy to read and is best zoomed in to 150%.

The manual is dated July 1959 with additions in September 1960. It was the property of Tony Gibbons who kindly donated it to us.