Associative processor

• US 4,254,476 A
• Filed: 06/25/1979
• Issued: 03/03/1981
• Est. Priority Date: 06/25/1979
• Status: Expired due to Term

• Current Assignee: Sanders Associates, INC. (BAE Systems Plc)
• Original Assignee: Sanders Associates, INC. (BAE Systems Plc)
• Inventors: Burrows, James L.
• Primary Examiner(s): Fears, Terrell W.
• Application Number:
  US06/051,468
• Time in Patent Office: 617 Days
• Field of Search: 365/49, 365/189, 307/238, 364/513, 371/10
• US Class Current: 365/49.1
• CPC Class Codes: G06F 16/9014 hash tables

Abstract

An associative processor for searching data stored in memory to identify messages or other data containing operator selected keywords containing alpha-numeric or other characters is disclosed. The identified messages or other data are then transferred from the memory to an output device for review. The processor comprises a plurality of commercially available integrated circuit random access memories (RAMs) for performing processing functions. The binary words read out of the RAMs are applied via a register to the higher order addressing inputs of the same RAMs without any processing. Messages being searched for keywords are applied to the lower order addressing inputs of the same RAMs. A binary word applied to the higher order addressing inputs of the RAM memory selects a block of memory bits with each bit being associated with a different character. Only memory bits within a selected block of memory bits corresponding to keyword characters being searched for contain binary words indicating the block of bits for the subsequent keyword character to be searched for. When a character being searched for is detected, the binary word in the corresponding memory location is read out and applied to the higher order memory inputs via a register. This causes the next block of memory bits to be addressed to await receipt and detection of the next keyword character. After detecting all the characters of a keyword, an output is provided from the RAM memory which causes the stored message containing the selected keyword or words to be transferred to the output device for operator review.

Claims

1. Apparatus for processing binary information comprising

a first memory having a first and a second section each of which are divided into blocks of memory bits in which are stored binary words, said stored binary words are read out of both said sections responsive to memory addressing information made up of binary words previously read out of said first memory section and binary bit codes within said binary information being processed, each of said binary bit codes respresenting a character;

binary words are written into said first memory for each character of preselected character sequences being searched for within said binary information, and one binary word for more than one preselected character sequence can be stored in a common memory block,

a first register for storing binary words read out of said first section of said first memory and then applying said stored binary words to addressing inputs of said first memory, and

enabling means responsive to binary words read out of said section section of said first memory for enabling said first register to store a binary word read out of said first section only for the next character of a particular character sequence and not for any other character.

2. The invention in accordance with claim 1 wherein said enabling means comprises

a second memory from which binary bits are read out responsive to said addressing information, said binary words read out of said second section of said first memory being applied to a first portion of addressing inputs of said second memory and the previous word read out of said second section of said first memory being applied to a second portion of said second memory addressing inputs, said binary bits read out of said second memory being applied to said first register to enable it to store binary words read out of said first section of said first memory only for the next character of said particular character sequence and not for any other character.

3. The invention in accordance with claim 2 wherein said enabling means further comprises a second register for storing binary words read out of said second section of said first memory and applying same to said second portion of said second memory addressing inputs, the contents of said second register being overwritten by subsequent binary words read out of said second section of said first memory.

4. The invention in accordance with claim 3 wherein said second register stores less than all the bits of the binary words read out of said second section of said first memory but the non-stored bits are applied to the first portion of said second memory addressing inputs and are used to distinguish between preselected character sequences having common characters or having character sequences identical with but less than all the characters in another preselected character sequence.

5. The invention in accordance with claim 3 wherein said binary information comprises messages that are to be checked with said processing apparatus to determine which of said messages contain preselected words or strings of words.