Glossary
A-4
S
shifter:
A hardware unit that shifts bits in a word to the left or to the right.
sign extension:
An operation that fills the high order bits of a number with
the sign bit.
W
wait state:
A period of time that the CPU must wait for external program,
data, or I/O memory to respond when reading from or writing to that ex-
ternal memory. The CPU waits one extra cycle for every wait state.
Z
zero fill:
A method of filling the low- or high-order bits with zeros when load-
ing a 16-bit number into a 32-bit field.
Glossary