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Cyhist Apr 15 1997 M
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Date: Tue, 15 Apr 1997 23:15:56 -0400
Reply-To: "CYHIST Community Memory: Discussion list on the History of
Cyberspace" <CYHIST@MAELSTROM.STJOHNS.EDU> Sender: "CYHIST Community Memory: Discussion list on the History of
Cyberspace" <CYHIST@MAELSTROM.STJOHNS.EDU> From: "E." <eray@ORA.COM>
Subject: Book: Computers in Space
X-cc: greg@earthweb.com
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Community Memory: Discussion List on the History of Cyberspace ______________________________________________________________________
I found an excellent book in a bargain basement store (which means it's probably out of print :-( ) by James Tomayko, called "Computers in Space, Journeys with NASA" (Alpha Books, 1994). It has all kinds of cool trivia about the computers used in the early space missions, like Apollo, Gemini, etc. It includes detailed schematics and pictures of the interfaces, which were pretty primitive. There are also amusing (or disturbing) stories about how syntax errors resulted in rockets exploding, etc.
My favorite is the Gemini navigation computer. It had 4000 39-bit "words" of ferrite core memory and word was divided into 3 syllables of 13-bits each. This was divided into 18 sectors. Each instruction was 13 bits and each datum was 26 bits (data could only be stored in the first 2 syllables of a word). To execute a program, the computer would execute all the instructions in the first syllable, then all the instructions in the second syllable, then all the ones in the third, then move to the next sector. If there was data in the way, there would have to be an instruction to jump over it. And to make matters worse, the programs were written in octal numbers by hand and maintained the same way. The only good news was that ferrite core memory is not volatile. ;-)
--
/\\ Erik T. Ray /\\
/--\\ O'Reilly & Associates /--\\
/_\\/_\\ makers of low-fat, high-protein books /_\\/_\\
(phone: 617-499-7449 - web: www.ora.com/people/staff/eray - opinions: mine)
computer-generated nonsense:
The warped, twisted pop megastar Michael Jackson, on the deck of an ancient Phoenecian trireme, plays the violent computer game Quake with unrestrained pleasure.
______________________________________________________________________
Reply-To: "CYHIST Community Memory: Discussion list on the History of
Cyberspace" <CYHIST@MAELSTROM.STJOHNS.EDU> Sender: "CYHIST Community Memory: Discussion list on the History of
Cyberspace" <CYHIST@MAELSTROM.STJOHNS.EDU> From: "E." <eray@ORA.COM>
Subject: Book: Computers in Space
X-cc: greg@earthweb.com
______________________________________________________________________
Community Memory: Discussion List on the History of Cyberspace ______________________________________________________________________
I found an excellent book in a bargain basement store (which means it's probably out of print :-( ) by James Tomayko, called "Computers in Space, Journeys with NASA" (Alpha Books, 1994). It has all kinds of cool trivia about the computers used in the early space missions, like Apollo, Gemini, etc. It includes detailed schematics and pictures of the interfaces, which were pretty primitive. There are also amusing (or disturbing) stories about how syntax errors resulted in rockets exploding, etc.
My favorite is the Gemini navigation computer. It had 4000 39-bit "words" of ferrite core memory and word was divided into 3 syllables of 13-bits each. This was divided into 18 sectors. Each instruction was 13 bits and each datum was 26 bits (data could only be stored in the first 2 syllables of a word). To execute a program, the computer would execute all the instructions in the first syllable, then all the instructions in the second syllable, then all the ones in the third, then move to the next sector. If there was data in the way, there would have to be an instruction to jump over it. And to make matters worse, the programs were written in octal numbers by hand and maintained the same way. The only good news was that ferrite core memory is not volatile. ;-)
--
/\\ Erik T. Ray /\\
/--\\ O'Reilly & Associates /--\\
/_\\/_\\ makers of low-fat, high-protein books /_\\/_\\
(phone: 617-499-7449 - web: www.ora.com/people/staff/eray - opinions: mine)
computer-generated nonsense:
The warped, twisted pop megastar Michael Jackson, on the deck of an ancient Phoenecian trireme, plays the violent computer game Quake with unrestrained pleasure.
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