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[Dave Philipsen]

Yes, it would be best to use one of those ribbon cables with double the 
number of conductors where every other conductor is a ground and keeping 
the length of the cable as short as possible.  However, 2 MHz is a 
fairly slow bus speed and I believe the old IDE drives carried signals 
at speeds of around 33 MHz on ribbon cables without too much of a problem.

Dave

On 1/4/2017 12:20 PM, RETRO Innovations wrote:
> On 1/4/2017 12:08 PM, Dave Philipsen wrote:
>> Internally there are multiple devices being driven by the address 
>> lines.   I have seen many implementations of devices all sitting on 
>> the same unbuffered bus of an 8-bit CPU system (usually in a card cage).
> The 'fanout' of TTL gates is 10, though CPUs typically are higher, 
> since lots of things will connect to address and data lines. Coupled 
> with using advanced logic (LSTTL creates 1/10th the load on the line 
> as normal TTL, for instance), and you could (and would) see 20 ICs 
> hanging on the address and data lines without issue.
>
> Noise is probably the larger issue.  An unbuffered address or data 
> line on a cart port is an antenna...
>
> Jim
>
>