[SiriusHardware]

Well done on the project - (I spy an Arduino?)

Running your test without a device in the test socket ought to produce a 'fail' result so you can see your failure message routines working, or you could force specific errors for test purposes by bending a selected address or data pin out horizontally so it doesn't make contact with the test socket. (Or just pull the relevant wire out of the breadboard)

Have you included some kind of overcurrent detection / protection? From what Jay said, this is likely to be something which will come up from time to time.