Abstract: In a display terminal equipment, a display device and a plurality of input devices are connected to a controller. Each input device is operated by an operator for inputting information. The controller controls the information entered from a different input device to be displayed on a different display area of the display device. It becomes possible for a plurality of operators to share a single display device and a single display terminal equipment while handling his or her own input device at the same time.

Abstract: An operation processing apparatus executes an instruction accompanied by addition/subtraction for one word and halfword operands at a high speed. An expander expands the sign of a second operand in its upper halfword bits to produce an expanded second operand having the same length as that of a first operand. An arithmetic unit operates the first operand and the expanded second operand.

Abstract: An arithmetic logic unit processes a variable operand length instruction such as a decimal arithmetic operation instruction, a plurality of bytes at a time using a multi-byte depth arithmetic operation unit. Multi-byte data including first and second operands are supplied to the arithmetic logic unit through a suppressing circuit. The suppressing circuit suppresses unnecessary bytes other than operand bytes and suppresses all of the bytes of one of the operands when the one operand has been exhausted.

Abstract: A data processing system has an arithmetic operating unit to process a plurality of bytes at a time and carries out an arithmetic operation on first and second operands each starting from any desired address on a main memory and having any desired number of byte length. The second operand is aligned to an operand position of the first operand and the aligned second operand is supplied to the operating unit while the first operand is supplied as it is to the operating unit. Since the second operand is aligned to the operand position of the first operand before it is processed in the operating unit, the number of times of alignment is reduced.