The labels you mention refer to the individual lines of a bus, specifically the address bus in this case. By definition, these go to several things in parallel. The A0-A15 coming off the processor though may not go directly to the other A... lines in a larger system. For example, in the Apple II, when memories were small and it took a ton of them to get 32K or 64K of RAM and ROM, a bus driver was used between the processor and everything else, as the processor alone could not drive such a heavy load.
In smaller systems that are more likely to be home-made, the bus drivers are normally unnecessary, so all the A0's would be connected together, for example.
If you're new to microprocessors, the 6502 family offers an easy place to start learning, and an excellent power-to-complexity ratio. You're bound to get hooked.
Garth Wilson
_________________ http://WilsonMinesCo.com/ lots of 6502 resources The "second front page" is http://wilsonminesco.com/links.html . What's an additional VIA among friends, anyhow?
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