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D.Duck D.Duck is offline
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First recorded activity by BoatBanter: Dec 2006
Posts: 1,533
Default 1956 IBM hard drive


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On Tue, 4 Dec 2007 17:09:22 -0500, "D.Duck" wrote:

The IBM 350 disk system stored 5 million 8-bit (7-bits plus 1 odd parity
bit) characters (about 4.4 MB).

http://en.wikipedia.org/wiki/IBM_305


Somebody needs to fix the Wiki.
It was 7 bits (remember the "odd parity"?)
The bits are 1, 2, 4, 6, A, B and parity.
It goes with "7 track tape" etc.


Here's from the horse's mouth:

"The 305 RAMAC is an entirely new machine which contains its own input and
output devices and processing unit as well as a built-in 5-million-digit
disk memory. Both machines operate according to a program of electronically
stored instructions."

http://www-03.ibm.com/ibm/history/ex...0/650_pr2.html