Memory Barriers
Memory-mapped I/O is the cause of memory barriers in older generations of computers. The 640 KiB barrier is due to the IBM PC placing the Upper Memory Area in the 640–1024 KiB range (of its 20-bit memory addressing).
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Famous quotes containing the words memory and/or barriers:
“‘I’m sorry that I spelt the word:
I hate to go above you,
Because’Mthe brown eyes lower fell—
‘Because, you see, I love you!’
Still memory to a grey-haired man
That sweet child-face is showing.
Dear girl! the grasses on her grave
Have forty years been growing.”
—John Greenleaf Whittier (1807–1892)
“Developing the muscles of the soul demands no competitive spirit, no killer instinct, although it may erect pain barriers that the spiritual athlete must crash through.”
—Germaine Greer (b. 1939)