class XTimesXTester extends [[OrderedDecoupledHWIOTester]] {
  val device_under_test = new XTimesY
  test_block {
    for {
      i <- 0 to 10
      j <- 0 to 10
    } {
      input_event(device_under_test.io.in.x -> i, device_under_test.in.y -> j)
      output_event(device_under_test.io.out.z -> i*j)
    }
  }
}

an input event is a series of values that will be gated into the decoupled input interface at the same time an output event is a series of values that will be tested at the same time independent small state machines are set up for input and output interface all inputs regardless of interfaces are submitted to the device under test in the order in which they were created likewise, all outputs regardless of which interface are tested in the same order that they were created