Re: LZ: NEW Z80 INSTRUCTION FOUND!!


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Re: LZ: NEW Z80 INSTRUCTION FOUND!!



On Thu, 26 Sep 1996 14:36:45 -0500 (CDT), you wrote:
>There are a lot of undocumented Z80 opcodes.  At least there were.
>They worked in all the Zilog made Z80's but I understand the TI's
>use an Hitatchi made Z80, so who knows if they'll work in it.
>
>I used to have a list of them but I haven't seen it for a few years.
>I'll look around and see if I can come up with it.


The reason they're undocumented is because when the Z80 was originally
manufactured, certain instructions worked only a percentage of the
time.  Since they didn't want to spend years refining the design, they
simply didn't document the instructions that didn't work all the time!


-Mel


<pre>
--
The TI-85 Memory Expantion Homepage
http://pilot.msu.edu/user/tsaimelv/expander.htm
</pre>


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