Question re booting a 68000 CPU

What are the essential signals required by a 68000 CPU in order to get
its address lines active?

Obviously Clock and Reset - but what else MUST be functional?

I ask as I repair arcade PCBs and usually concentrate on 6502, 8080
and Z80 boards. However I've recently starting fixing up a few
68000-based boards from the late 80s/early 90s and a few, despite
having valid Clock and Reset signals, are doing absolutely bugger all,
ie no activity on any address lines, etc.

Now a 6502, 8080 or Z80 will fire up the address lines if they have
valid Clock and Reset signals, but apparently this isn't the case with
the 68000. Or is it? Does it also need to grab a valid piece of boot
code from a connected ROM or EPROM?

Ta!

.

Relevant Pages

  • Re: Mixed clocked/combinatorial coding styles
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  • Re: Problem with simple VHDL piece of code
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  • Re: Event Driven State Machine
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  • Re: if and and vs if and,and
    ... signal reset: std_logic; ... elsif rising_edge (clock) then ... signals event, in sensitivity list. ...
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  • Re: Question re booting a 68000 CPU
    ... Obviously Clock and Reset - but what else MUST be functional? ... having valid Clock and Reset signals, are doing absolutely bugger all, ... The NOP instruction is *not* all zeros, but if you stuff the bus with zeros, it should accept the vector table and execute OR instruuctions with one of the registers till the cows come home. ...
    (sci.electronics.misc)