- What happens if you give the Intel 8086 processor an instruction that doesn’t exist? A modern microprocessor (80186 and later) will generate an exception, indicating that an illegal instruction was executed. However, early microprocessors didn’t include the circuitry to detect illegal instructions, since the chips didn’t have transistors to spare. Instead these processors would do something, but the results weren’t specified.
- NGC 663 (Wikipedia)
NGC 663 (also known as Caldwell 10) is a young open cluster in the constellation of Cassiopeia. It has an estimated 400 stars and spans about a quarter of a degree across the sky. It can reportedly be detected with the unaided eye, although a telescope is recommended for best viewing. The brightest members of the cluster can be viewed with binoculars. Although the listed visual magnitude is 7.1, several observers have reported higher estimates.
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