Method for testing a device ready for operation

摘要

The device can be the time-division multiplex switching network (ZMK) of a digital telephone switching device (ZV). This can be connected via appropriately constructed connectors (SV) to a processor-controlled test device (PE) carrying out the test. It is intended to prevent any changes from occurring in the connections existing between the hardware parts in the completely equipped device under test. For the comparison of a nominal signal sequence with the actual signal sequence which can be picked up at a correspondingly selected circuit point, which comparison forms the basis of the test, the digital nominal signal sequence is therefore picked up at a suitable circuit point and supplied to the test device in cases in which this nominal signal sequence cannot be directly provided by the test device for reasons of an undisturbed sequence. In the case of the digital switching device, the digital signal sequence is used which is produced at the output of the analog/digital converter (Co) on the basis of the analog input information supplied to it. This ensures that no undefined signal state exists for the respective input chip of the switching network to be tested. At the same time, this makes it possible to eliminate inadmissible heating of the output stages of the said converter. <IMAGE>