Data processing system incorporating a memory resident directive for

Abstract

In a data processing system of the type including a plurality of processing elements interconnected with each other and with a plurality of memory elements by an interconnection means, a method is provided for accommodating the accessing of a selected memory location in a selected one of the memory elements by at least one requesting processing element to read data stored thereat. The method thereby permits the communication of information between the plurality of processing elements. The method comprising the steps of: sending, from the requesting processing element to the selected memory element via the interconnecting means, a directive including (1) the address of the selected memory location, (2) a comparison value, and (3) an identification of the requesting processing element sending the directive; reading in the selected memory element the data stored at the selected memory location; comparing in the memory element the read data with the comparison value; notifying the requesting processing element via the interconnection means if the read data matches the comparison value; storing the directive in the selected memory element if the read data does not match the comparison value; and repeating the reading, comparing, and notifying steps each time the data in the selected memory location is altered.