Re: [hatari-devel] Falcon booting problem?

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

HI,

On torstai 27 elokuu 2015, Nicolas Pomarède wrote:
> Le 26/08/2015 21:48, Eero Tamminen a écrit :
> > Hi,
> > 
> > Falcon booting doesn't work for me anymore.  I get invalid Videl
> > line width register values (which crashed Hatari before I commited
> > a check for that [1]).
> > 
> > Does somebody else have the same issue and if yes, any idea what
> > causes the bogus register value?
> > 
> > [1]
> > http://hg.tuxfamily.org/mercurialroot/hatari/hatari/rev/d1b01a6bf36f
> 
> booting works for me. Did you try with an empty config file to get
> default values?  Maybe your using a different monitor setting or some
> extended VDI resolution ?

I had tried with defaults (hatari.cfg removed) and re-building
everything from scratch.  Same problem, also with oldUAE.


> did you try doing a "b (ff8210).w ! (ff8210).w" to see where the value
> gets changed to 0 ?

This is the place where videl.c reports $8210 to get value 0xc00,
which is same as zero (when it's ORed with 0x3ff):

$00e083d0 : 307c 820e                          movea.w   #$820e,a0
$00e083d4 : 30b9 0000 1866                     move.w    $1866,(a0)
$00e083da : 307c 8210                          movea.w   #$8210,a0
$00e083de : 30b9 0000 1868                     move.w    $1868,(a0) <===
$00e083e4 : 307c 82c2                          movea.w   #$82c2,a0

I.e. the value that TOS puts there according to disassembly
is different than what Videl trace tells:
Videl : $ff820e Line Offset write: 0x0000
Videl : $ff8210 Line Width write: 0x0c00
<breakpoint triggers here>
Videl : $ff82c2 Video Mode (VDM) write: 0x0004
Videl : $ff82c0 Video control (VCO) write: 0x0081
Videl : $ff8266 Falcon Shift Mode (SPSHIFT) write: 0x0000

And 0x1868 & 0x3ff = 104, not zero.  WTF?


	- Eero