11 Jun
2006
11 Jun
'06
9:44 p.m.
> I can't think of any other reasons. Are
there any?
Debugging. particularly on prototypes. For example, I've been known to
pull the data bus buffer next to the CPU (assuming everything else is on
the other side of the buffer to the CPU) and force the CPU to execute
NOPs. Then I get a nice incrememting count on the address bus (with most
CPUs, anyhow :-)), and can see that address decoder outputs, etc, behave
correctly.
Or if you have a data line stuck, you can pull chips connected to the bus
until it starts behaving, then look to see why that's always outputting.
-tony