Relic Information query matches
Matching on query: Unique id = 149/00, Name = any, Associated machine = any, class = any
Unique id/year of acquisition: 149/00
Name: EDSAC coding pad
Photograph not applicable
Other nos on object: none
Inscription: UNIVERSITY MATHEMATICAL LABORATORY, CAMBRIDGE EDSAC PROGRAMME SHEET
Description: Cardboard backed pad of paper forms, each of which has a printed grid with numbered rows and columns headed Order and Notes
Machine: EDSAC I
DW: These programming pads were used for EDSAC 1. Maurice [Wilkes] had a large number printed and they were in common use. Programs were made of a main program and subroutines, each starting with a fresh sheet. The numbering started with zero on each set of sheets,the directive GK resetting the references. Every tenth location was usually filled in. This meant that most references were local and simple faults did not lead to renumbering the entire program. A typical way of programming was to first write the function letters known addresses. A second scan would enable the programmer to fill in all the local references.
After a program was complete it would be taken to a keyboard punch to make paper tape (5 hole). The separate parts of the program would be copied by a tape reader tape punch combination onto a single tape including the needed library routines. The results were often checked using a tape comparater which had two tape readers and stopped when the tapes were different. As the tapes were translucent, some people compared the tapes by superposing in alignment, holding up to the light and looking.
This would then be taken to the computer to be run. The results were punched on a paper tape and printed by an offline reader-teleprinter combination.
See also: 1/97
Number of matches = 1
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