A86: Re: Assembly-86 Digest V1 #847


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A86: Re: Assembly-86 Digest V1 #847




> Date: Sun, 28 Mar 1999 20:16:53 EST
> From: ComAsYuAre@aol.com
> Subject: Re: A86: _vputs
> 
> actually, the z80 is a sort of backwards chip, so when you do "ld
> (_penCol),bc" c is loaded into _penCol and b is loaded into _penCol+1, which
> in this case is _penRow
> 
> it stores addresses with the least significant byte first, so 16 bit access to
> memory is reversed.
> 
> for example, the opcode
> call $4598
> is stored in hex as
> $cd9845
> 
> jp $409c
> is stored in hex as
> $c39c40
> 
> you'll get used to it.
> 
> In a message dated 3/28/99 8:12:25 PM Eastern Standard Time, v8r@juno.com
> writes:
> 
> > Let me make sure I have this straight..
> >
> >  _penCol and _penRow are both controled by a byte each in memory...
> >
> >  They are right next to eachother so by using ld (_penCol), bc you are
> >  saying load the byte at (_penCol) with b and then load the next byte
> >  (which happens to be _penRow) with c...
> >
> 

I resent the z80 chip being called backwards!  Indeed, it is other
chips, those chips who break their eggs at the big end, who are the
backwards ones!  It is calculated that some 40,000 chips have suffered
death rather than store their numbers in the lesser-greater format.

--Bill Barksdale


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