Abstract: The present invention provides an automotive test diagnostic system which is capable of achieving high data rates through multiple, independent instrumentation channels. The test diagnostic system includes a vehicle diagnostic instrumentation controller, the vehicle diagnostic instrumentation controller comprising: an instrument peripheral interface means; an instrumentation control means, the instrumentation control means being further comprised of an arbitration control means, and a device interface means, wherein the arbitration control means is electrically coupled to the device interface means; and a first bus for electrically coupling the instrument peripheral interface means to the instrumentation control means. In the preferred embodiment, the instrumentation control means further includes a data qualification means and a data storage means for storing data. However, dependent on the rate of data transfer, the calculations required, etc.