Page 47 - DCAP101_BASIC_COMPUTER_SKILLS

Basic Computer Skills

Notes
Figure 3.5: Cache Memory

Cache
Memory

What is different between catch memory and RAM?

Timeline of Computer Memory

1834: Charles Babbage begins build his ‘‘Analytical Engine’’, Precursor to the computer.
It uses read-only memory in the form of punch cards.
1932: Gustav Tauschek invents drum memory in Austria.
1936: Konrad Zuse applies for a patent for his mechanical memory to be used in his
computer. This computer memory is based on sliding metal parts.
1939: Hepmut Schreyer invents a prototype memory using neon lamps.
1942: The Atanasoff-Berry Computer has 60 50-bit words of memory in the form of
capacitors mounted on two revolving drums. For secondary memory it uses punch
cards.
1947: Frederick Viehe of Los Angeles, applies for a patent for an invention that uses
magnetic core memory, Magnetic drum memory is independently invented by
several people.
1949: Jay Forrester conceives the idea of magnetic core memory as it is to become
commonly used, with a grid of wires used to address the cores. The first practical
form manifests in 1952-53 and renders obsolete previous types of computer memory.
1950: Ferranti Ltd. completes the first commercial computer with 256 40-bit words of
main memory and 16K words of drum memory. Only eight were sold.
1951: Jay Forrester files a patent for matrix core memory.
1952: The EDVAC computer is completed with 1024 44-bit words of ultrasonic memory.
Acore memory module is added to the ENIAC computer.
1955: An Wang was issued U.S. patent #2,708,722 with 34 claims for magnetic memory
core.
1966: Hewlett-Packard releases their HP2116A real-time computer with 8K of memory.
The newly formed Intel starts sell a semiconductor chip with 2,000 bits of memory.
1968: USPTO grants patent 3,387,286 to IBM’s Robert Dennard for a one-transistor DRAM
cell. DRAM stands for Dynamic RAM (Random Access Memory) or Dynamic
Contd...

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