Circuit for setting a device into a test mode by changing a first port to a fixed clock and a second port to a non-fixed clock

摘要

An apparatus for setting a device into a test mode. The apparatus has a first input port for receiving a fixed, constant signal during a normal mode of the device, and for receiving a non-fixed, clocked signal so as to set the device into a test mode. The apparatus also has a second input port for receiving a non-fixed, clocked signal during the normal mode and for receiving a fixed, constant signal so as to set the device into the test mode. When both the first input port receives the non-fixed, clocked signal and the second input port receives the fixed, constant signal for a predetermined amount of time, the device is placed into the test mode.