I deleted the earlier message that talked about word sizes on old IBM mainframes before I remembered a couple of GREAT old references I keep in my bookcase:
"Computers" by Edmund C. Berkeley and Lawrence Wainright, copyright 1956. (Can't find an ISBN number on it for some reason :). On page 26, it includes the following: "In nearly all digital computers, information is regularly stored and handled in sets of a fixed number of characters, such as 36 binary digits, or 10 decimal digits and algebraic sign (equivalent to one more binary digit), or 12 characters, any one of which is expressed by 6 binary digits. A place in the computing equipment where such a word may be stored in appropriate hardware until needed, is called a register." As if some of those weren't fun enough to wrap ones' brain around, "Giant Brains or Machines that Think", an earlier work by Edmund C. Berkeley, copyright 1949 contains: "Basically, a number is represented in Eniac [earlier described as "another of the giant brains that has begun to work"] by an arrangement of on and off electronic tube elements in pairs, called flop-flops. There is one flip-flop enclosed in a single tube (type 6SN7) for each value 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 for each of the 10 digits stored in an accumulator." (FYI: A PANEL was dedicated per accumulator). Page 179 notes: "As this book went to press, another mechanical brain, the Electronic Binary Automatic Computer, or BINAC, was annouced [...] Binac has 512 registers of very rapid memory in mercury tanks, and each register holds 30 binary digits." So when anybody starts on about the "efficiency" of using smaller register sizes, I'm going to yank out a reference from back when "efficiency" was measured in the amount of work that could be done with a register that took up a full rack. Don't tell me 16 bits is better until you've soldered the additional tubes in place yourself! :) - Bob Mercury tank storage, anyone? To unsubscribe from SURVPC send a message to [EMAIL PROTECTED] with unsubscribe SURVPC in the body of the message. Also, trim this footer from any quoted replies. More info can be found at; http://www.softcon.com/archives/SURVPC.html
