Re: LZ: Help with a routine

Subject: Re: LZ: Help with a routine
From: KEITH T BURZINSKI <FFNP69C@prodigy.com>
Date: Fri, 20 Sep 1996 17:40:11, -0500
In-Reply-To: <LZ: Help with a routine>

>> Sure.  BIT is easy.  All it does is compliment the bit you test 
and 
>> then puts that in the zero flag.
>> For example:
>>     BIT 7,a
>> tests the MSB of the accumulator.  If the bit is 1, then the zero 


>> flag is cleared, indicating "not zero".  (Right?)  If the bit is 0,
 
>> then the zero flag is set, indicating "zero".
>> 
>> Got that?  ;)
>> --------
>> >I need to know how to use the BIT opcode... the
>> >specific routine requires me to test the MSB (first
>> >bit) of a byte and branch if it is 1.  Can someone
>> >please fill me in?
>> 
>> ____
>> ~Keith
>> FFNP69C@PRODIGY.COM
>> 
>
>Actually, I think that if the bit is set, it will set the ZERO 
>flag, but if it is cleared, then it will clear the Z flag 
(indicating 
>nz).
No, because if the zf is set, it indicates a zero result.
If a bit is set, it is not zero, so the zf is cleared...  Wait a 
minute.  Why argue?  Does anyone have a Z80 book that could check 
this out?


I don't like to flame,


____
~Keith
FFNP69C@PRODIGY.COM

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