IAS
1. <computer> The first modern computer. It had main registers,
processing circuits, information paths within the central processing unit, and
used Von Neumann's fetch-execute cycle.
The IAS machine's basic unit of information was a 40-bit word and the memory had
4096 words. A word stored in memory could represent either an instruction or
data. Each IAS instruction was twenty bits long, so that two instructions could
be stored in each 40-bit memory location. Each instruction consisted of an 8-bit
operation code and a 12-bit address that could identify any of 2^12 locations
that may be used to store an operand of the instruction.
The CPU consisted of a data processing unit and a program control unit. It
contained various processing and control circuits along with a set of high-speed
registers for the temporary storage of instructions, memory addresses, and data.
The main actions specified by instructions were performed by the
arithmetic-logic circuits of the data processing unit. An electronic clock
circuit was used to generate the signals needed to synchronise the operation of
the different parts of the system.
[Who? Where? When? Implemented using what?]
2. Immediate Access Storage.
(2003-10-24)
Nearby terms:
IAP « I-APL « IAR « IAS » IAW » IAYSDAH » IBEX
