Structured data files in a data driven digital data processor

Abstract

A character-serial electronic digital computer utilizing four character vocabulary, each character being represented by two binary bits, is structured to process character-serial data arriving at the computer in a manner specified and initiated by the arriving data. Data structures that may represent program or operations to be performed on data arriving at the computer input are stored in the computer's storage area in the form of nested data structures that may be illustrated as tree structures in which each node of the tree structure represents an operation. Data structures that may represent operands are also supplied to the computer in a nested organization. This operand data addresses a certain node or operation resident in the computer storage area. The linking up of the arriving operand data with its program data triggers execution of the operation. In a case where more than one operand is needed before an operation can be performed the arrival of a first operand without the second causes storage of the first operand until arrival of the second. Arrival of the second operand triggers the operation to begin. This interrelationship of program data and operand data, that is, the dynamic data being linked with the static data to trigger the operation, exists whether the program data is stored and static or the operand data is stored and static. Utilizing a four character vocabulary, to represent data, two of the characters being utilized to indicate the beginning and end of a data field, facilitates the implementation of an error checking technique wherein only sensed characters indicating the beginning and end of a data field are counted. The utilization of beginning and end of data field characters in the data structures consisting of nested data fields permits at will expansion and contraction of the fields within it.