Patent ID: 7454681

Claim:
A test system, comprising: a) a reference clock generator providing a reference clock; b) a first instrument comprising i) a first local clock generator coupled to the reference clock generator and providing a first local clock generated from the reference clock, ii) a first control circuit storing programmed commands comprising at least one command to be executed by the first instrument and at least one command to be executed by a second instrument, and c) a second instrument comprising i) a second local clock generator coupled to the reference clock generator and providing a second local clock generated from the reference clock; ii) a second control circuit having an input and an output, the second control circuit asserting the output at a time specified by a time value provided at the input to the second control circuit; iii) functional circuitry having a control input coupled to the output of the second control circuit, the functional circuitry executing a function in response to a value asserted at its control input; and d) a network between at least the first instrument and the second instrument, the network carrying a message that includes a time value, wherein the first control circuit is coupled to the network to provide the time value in the message and the second control circuit is coupled to the network to receive the time value at its input.