Test set controlled by a remotely positioned digital computer

Claim 1

A test system, comprising in combination: a. a computer facility comprising means for generating a series of digital data words, said words specifying predetermined input signals to be used to test remotely positioned equipment and means for analyzing sample signals indicative of the response of said equipment to said predetermined input signals; b. a test set comprising (1) means for receiving said digital data words and for generating in response thereto said predetermined input signals, (2) means for coupling said predetermined input signals to said remotely positioned equipment, (3) means for sampling signals produced by said equipment in response to said predetermined input signals to generate said sample signals; and c. communication apparatus comprising first and second stations coupling said computer and said test set via a full duplex channel, said first station being positioned at said conputer and said second station being positioned at said test set, each of said stations including error correction means comprising: 1. a field code generator for generating and assigning a sequential field code to each of said digital data words at the point where said digital data words originate to form a data signal: 2. start code detector and temporary storage circuitry to detect when a data signal originating at the other station is being received and for storing a predetermined number of said data words and their associated field code; 3. data retransmitting means for transmitting the received digital data signal to the originating station; 4. compare means for comparing the retransmitted digital data signal to the original digital data signal on a bit by bit basis with any difference between these signals indicating a transmission error; 5. means for retransmitting any digital data signal found to contain errors without interrupting the data stream from the transmitting to the receiving station; and 6. means for checking the sequence of the field codes associAted with each of said data words as they are received by the receiving station to determine if the associated data word is being retransmitted because of transmission errors and for outputting data words from said temporary storage when the stored data word has been verified as correct by checking the sequence of field codes arriving at said stations.