MITS 2SIO serial chip? - test-drb@ccmp.vtda.org

20 Dec 2001

From: Ben Franchuk &lt;bfranchuk(a)jetnet.ab.ca&gt;
...
 One real problem with the Z80 is that a there is a lot
of
unused/undefined
instructions because of the complex instruction set, that have been
decoded
and used in software. This has a impact if you are not using a real chip
but a emulator of some sort.  

Most are either redundant or no-ops, those at are useful most good z80 
emulators have them as they are copied in competitors z80s.

Allison