Abstract: In a data processing system, groups of characters to be manipulated in a predetermined manner are transferred between storage units and a central processing unit by apparatus and a method which identifies and corrects a character of a group with sign information superimposed on an identified character position for data entering the central processing unit. After identification of the character position containing the sign information superimposed on a character position, the value of the character in the identified character position is determined by apparatus removing the superimposed sign information and such value is placed in such identified character position in the entering character group. A data string including an identified character position can then be entered in the execution unit of the central processing unit for execution of instructions.

Abstract: In a data processing system wherein memory space in a memory unit is divided into addressable locations capable of storing a group of signals of predetermined number called signal words, and wherein an entire word or groups of entire words are exchanged between the memory unit and a central processing unit, more efficient operation of the data processing unit can be obtained if groups of related signals called operands can be stored consecutively in the addressable locations without regard to the word boundaries. Thus, operand boundaries can have arbitrary positions in boundary words. When a word containing an operand boundary is transferred to the central processing unit, non-operand data is also transferred with the word. The non-operand data occurring in the boundary words is removed from the operand signal group and stored in the central processing unit.