On some m68k-based Texas Instruments graphing calculators, high memory addresses that go beyond the physical memory can be used to access the physical memory (the address space folds itself over the physical memory). This range of addresses is called ghost space, because it mirrors the actual physical space.
For TI-89 programmers, ghost space starts from address 0x40000, and it is widely used to circumvent some of the protections introduced with the HW2 (hardware version 2) release of the calculator. This became a compatibility issue with the release of HW3 (the Ti-89 Titanium), where it is disabled, and patching the ROM (HW3Patch) becomes necessary.
Famous quotes containing the words ghost and/or space:
“Her voice is thin and her moan is high,
And her cackling laugh or her barking cold
Bring terror to the young and old.
O Molly, Molly, Molly Means
Lean is the ghost of Molly Means.”
—Margaret Abigail Walker (b. 1915)
“The woman’s world ... is shown as a series of limited spaces, with the woman struggling to get free of them. The struggle is what the film is about; what is struggled against is the limited space itself. Consequently, to make its point, the film has to deny itself and suggest it was the struggle that was wrong, not the space.”
—Jeanine Basinger (b. 1936)