I know that the spec for the TEST pin on the HCS12xx says that the pin MUST be tied to gnd - but what could happen if it isn't ??
The reason for asking this is as follows. We have had some units out in the field that have passed all our normal test procedures, but a few months later have been having 'odd faults' - none of which we could really put our finger on. Then we noticed that a mistake has been made on the PCB, and the TEST pin has been left floating.
The two may not be related at all - I'm just exploring the possibility.
Does anyone know what happens in this case ?