Hi, We have circuit card having MC68302CFE16Care workin...

[fikret]

Hi,

We have circuit card having MC68302CFE16Care working  for repairing it. Although everthing EXTAL, XTAL, DISCPU, HALT, RESET, CS0-3   ..etc and  input clamping diodes All of them are OK  but there are no signal on address lines.  We tested output buffers connected to the address bus found that they are OK too . We disconnected one address line from the buffer  and saw still there is nothing on that address output .

Could you advise us what can be the problem or any idea why our CPU cannot start to operate?

[taigbr]

Hi Fikret,

I think there is a VCC connection missing that supplies power
to the drivers of the adr signals. So check the supply pins of the
68302.
Georg