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2

The earliest contender I can find is the Friden Flexowriter, from 1958. It was an electric typewriter with an attached paper tape reader and punch. You can see a video here. This is a restored Flexowriter, but the visible sign lists 1958 as the year it was presumably built. As you can see, this particular model uses 8 channel tape. The Flexowriter would ...


14

TL;DR: 5 hole (*1) tapes were developed as part of Murray's teletype system, the first (successful) to use typewriter keyboards as well as punch tapes. Wider (more holes) paper tapes are compatible enhancements thereof. There is no sole 'inventor' per se, as the 8 (+1) hole punch with fixed width tape of 1 inch is the logical extension of existing 5 hole ...


8

In addition to anotehr-dave's in depth answer maybe some (not PDP-1 specific) background information to show the environment: 8 hole punch tape was only a thing rather late on. Paper tape was commonly used in 5 to 8 hole versions (special types up to 24 and more), depending on purpose/equipment. 5 hole was 'small' Baudot type tapes, while 6 to 8 hole shared ...


7

This is explained here starting at page 21. There are basically two modes in which a paper tape can be used: Alphanumeric: 8 bits per tape line. Binary: 3 tape lines of 6 effective bits each per 18 bit word. Positions 7 and 8 are unpunched and punched respectively when punching. Lines with position 8 unpunched are skipped while reading. Instructions were ...


16

The answer is invariably specific for a particular computer, and indeed may be specific depending on what is doing the reading (say, hardware bootstrap versus software loader, or what it's reading from (say, photoelectric reader versus teletype attachment). On the PDP-1 reading 8-channel tape in binary mode from the photoelectric reader, an 18-bit word was ...


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