IBM 305 RAMAC

Herausgegeben:Miller, Frederic P.; Vandome, Agnes F.; McBrewster, John

• Broschiertes Buch

Produktbeschreibung

High Quality Content by WIKIPEDIA articles! The IBM 305 RAMAC, publicly announced on September 13, 1956, was the first commercial computer that used a moving head hard disk drive magnetic disk storage for secondary storage. RAMAC stood for "Random Access Method of Accounting and Control". Its design was motivated by the need for real time accounting in business. The first RAMAC to be used in the US auto industry was installed at Chrysler's MOPAR Division in 1957. It replaced a huge tub file which was part of MOPAR's parts inventory control and order processing system. The 305 was one of the last vacuum tube computers that IBM built. The IBM 350 disk system stored 5 million 8-bit 7-bits plus 1 odd parity bit characters. It had fifty 24-inch diameter disks. Two independent access arms moved up and down to select a disk, and in and out to select a recording track, all under servo control. Average time to locate a single record was 600 milliseconds. Several improved models were addedin the 1950s. The IBM RAMAC 305 system with 350 disk storage leased for $3,200 per month in 1957 dollars, equivalent to a purchase price of about $160,000. More than 1000 systems were built.

Produktdetails

• Verlag: Alphascript Publishing
• Seitenzahl: 76
• Englisch
• ISBN-13: 9786131657696
• ISBN-10: 6131657696
• Artikelnr.: 29778056