Patent GB-1170260-A (GB)
Title: Improvements in or relating to Control System Utilising an On-Line Digital Computer.
IPC: G06F9/308
Filed: 1966-12-13
Abstract: 1,170,260. Process control computer. SPERRY RAND CORP. 13 Dec., 1966 [15 Dec., 1965], No. 55801/66. Heading G4A. An on-line process control digital electric computer stores the individual operations to be performed during the process together with a programme consisting of sets of operations, which sets are compared serially in a predetermined order with the individual operations to determine groups of mutually non-conflicting operations which groups are performed consecutively. A serial computer storing a programme on a magnetic drum receives, for instance, machining information defining the size and depth of a hole to be drilled, from a tape reader. The information is processed and commands produced. A control " characteristic " word is established in the memory having individual digits representing the desired responses the machine is capable of making. The " characteristic " word is called from memory and loaded into the data accumulator and compared with a series of " mask " words also called from memory. Each mask word consists of individual digits representing compatible machining operations which, if called for can be performed substantially at the same time without mutual interference. The comparison of the first " mask " word with the " characteristic " word produces an " extract " word having ones in positions where both the " mask " and " characteristic " words have ones. The " extract " word represents the machine responses to be performed in a group at substantially the same time. Provision is made for initiating a respective output routine for each binary one in the " extract " word and for monitoring the completion of the output routine. As each response is completed the binary one in the " characteristic " word is deleted. The process is repeated with a second " extract " word when all the appropriate ones have been deleted. Lines of upcoming data can be read and processed during the time that the computer is awaiting completion of the output routine. The characteristic word can be divided into separate portions processed in sequence. Figures 2a, 2b show the order of operation for a two part " characteristic " word. The first " characteristic " word is loaded 46, compared with the " mask " to define an " extract " word which is tested to see if any bit is a " 1." If the word comprises all zeros then the second part of the " characteristic " word is loaded 50. If not the word is circulated one position to test for the first " 1." If a " 1 " occurs the response routine is initiated and the above process repeated. On the repeat the same " 1 " is tested. The test is now for completion of routine and assuming the routine has not been completed a " 1 " is found (line 46) and the " extract " word is circulated 4 bits. This assumes that the next three bits would not be required since all possible operations are usually not performed. This is tested for " 1 " and causes another loop to be performed, the procedure continuing for all the " 1's " existing in the first " characteristic " word. If any routine is completed during the operation of the loops then the sense completion 0 and delete bit routine are entered causing the appropriate " 1 " in the " characteristic " word to be deleted and the loop to be recirculated. A similar routine is followed for the second " characteristic " word. If all operations have been initiated but not completed line 60 is followed to cause a tape read bit to be extracted from the " characteristic " word. This is a " 1 " if an entire block of tape data read routines are initiated. If all the responses of the second " characteristic " word are completed the first card is checked for the presence of a " 1 " other than tape read (63, 69, 65, 62) and the loops are continued if a " 1 " exists, otherwise bit 12, indicating whether more " mask " words are to be used, is tested. If it is " 1 " there are no more words, reading of tape is completed and the process stops, otherwise the procedure repeats with the new " mask " words. The operation of the computer is described with respect to Figs. 3a-3cc (not shown, including the operation of the serial full adder, the instruction decoding, the timing, the accumulator, the comparator and the timing pulse generators.