[A86] Re: ROM / RAM equates database


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[A86] Re: ROM / RAM equates database




> Van: rabidcow@juno.com
> 
> On Mon, 24 Sep 2001 08:51:39 +0200 "Henk Poley" <HPoley@DDS.nl> writes:
> > 
> > Ti86 points to. For a very basic example, $4000 (_ldhlind / 
> > LD_HL_MHL) on the Ti83 always points $0033. 
> > There might be more... 
> 
> That particular routine is at $0033 on *all* calcs, from the 82 to the
> 73. I wouldn't be surprised if most of the rst's were the same, too.

Okay, I know, but the problem is I didn't know the entrypoint(s) of the
other calcs...

> > Plus the possibility to speed up programs per different ROM. I know 
> > that everybody I tell this kind of stuff says "when you use ROM
> > routines, you know they are slow, so it is better to implement the
> > routines yourselves if you want speed.", <sigh>.
> 
> It would be amusing if someone were to rewrite the rom for speed (test it
> with vti) and send a copy to ti.

That would take you years to unroll all these stupid loops and jumps..

Code below is an example of programflow you find quite often in the Ti
ROMs...

Label1:
	ld	a,(de)
	ld	(hl),a
	inc	de
	inc	hl
Label2:
	ld	a,(de)
	ld	(hl),a
	inc	de
	inc	hl
Label3:
	ld	a,(de)
	ld	(hl),a
	inc	de
	inc	hl
Label4
	ld	a,(de)
	ld	(hl),a
	inc	de
	inc	hl
	ret

	[..]

OtherLabel1
	ld	a,(de)
	ld	(hl),a
	inc	de
	inc	hl
OtherLabel2
	ld	a,(de)
	ld	(hl),a
	inc	de
	inc	hl
OtherLabel3
	ld	a,(de)
	ld	(hl),a
	inc	de
	inc	hl
	jp	Label1

Optimizing with LDIR would be an option I think...

	Henk Poley <><