Conclusion

The most important lesson I have learned during this project was never to use
74HCT ICs for driving backplanes, especially when a big electronics company
from the Netherlands somehow was involved in the production process of said ICs.

For driving backplanes, better resort to old (non_RoHS conform) 74LS/74ALS
parts, manufactured by Fairchild or TI.
...Shrinking chip geometries isn't always a good thing.

If you happen to buy 74LS parts in DIP package (especially those with a
readable engraving on top of the case), buy plenty of them like if it would
be your last chance, maybe because it really could be your last chance.

Same thing for RAMs in DIP package, especially fast RAMs.

When buying IC sockets and connectors, don't save money on the wrong end,
it isn't worth the trouble.

Don't buy cheap power supplies.
If you happen to have an adjustable power supply and want to use it for your
TTL hobby projects, better check if it delivers a spike of more than 5V at
the output when switching it on/off.

Chances are low to build something like a 68k compatible TTL CPU at home,
but it might be possible to build something running at more or less
the same speed as a 16 MHz 68000.

...and a 16 MHz 68000 is capable of running uClinux.

There is a chance of building an open hardware platform, able to run some
serious software...
but there always are two important questions questions:
1) Is it future proof ?
2) Is it worth the trouble ?

TTL hobby computing takes a lot of time and effort to build.

I somehow doubt that more than a handful of people will show serious
interest in TTL hobby computing, except for the academic value.
(Teaching students how a computer works in detail).

There is a difference between looking at some computer related exhibits
in the showcases of a university, and trying to build your own TTL CPU.

And it's nearly as big as the difference between watching the remains
of dead wales in a museum, and suddenly finding yourself standing on
deck of a tiny ship on the big ocean in midst of heavy sea and really
bad weather while someone is shouting "MAN THE HARPOON !"
into your ears.

In both cases, there is a chance of reaching a point where you refuse
to eat something like fish for the rest of your life.

Building a 32 Bit TTL CPU was fun, but it's more a full time job for
(at least) two engineers rather than a spare time project for a lone,
little hobbyist.

As in Charlie Chaplin's "Modern Times", the modern world of working contracts
(or working conditions) doesn't seem to leave much spare time for hobby projects
anymore.
If you have thoughts about to do your electronics hobby for a living
(maybe after reading some articles), please think again.

That's all for now.

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