I know msel0 and msel1 should be connected to VCC or GND.
but I forgot to connect them. when I debug the PCB,the cyclone ii device become very hot quickly! :( can it because of the "msel problem"? :all VCCIO = 3.3,VCCINT = 1.2.
Is it a custom board ? Msel problems ? I don't know. You can make a "service request" on Altera web site. the cyclone ii device become very hot quickly if there are short-circuits with your board. Have you configured unused pins as "input tri-stated" ? By defaut, it is "output driving GND" which is a bad ideea in my opinion.
The Cyclone II datasheet is very clear about the need for connecting MSEL pins. In so far, a service request surely won't get the answer ist's O.K. It's different e.g. with Cyclone III, that has pull-down resistors for MSEL.
I would also rather expect I/O shorts to cause excessive power dissipation. But I can't exclude, that the problem may be caused by unconnected MSEL.
