[hatari-devel] Videl changes

Laurent Sallafranque laurent.sallafranque at free.fr
Sat Feb 5 23:16:37 CET 2011


I Just have a question : is it possible to change the HBB and HBE 
(border begin and border end) registers in the middle of the screen (HBL 
change) or is it just taken into account by the Videl during each VBL ?

Same question for other parameters (horizontal and vertical parameters) ?

List of registers implied by my question below:

     $FFFF8280 (word) : HHC - Horizontal Hold Counter
     $FFFF8282 (word) : HHT - Horizontal Hold Timer
     $FFFF8284 (word) : HBB - Horizontal Border Begin
     $FFFF8286 (word) : HBE - Horizontal Border End
     $FFFF8288 (word) : HDB - Horizontal Display Begin
     $FFFF828A (word) : HDE - Horizontal Display End
     $FFFF828C (word) : HSS - Horizontal SS
     $FFFF828E (word) : HFS - Horizontal FS
     $FFFF8290 (word) : HEE - Horizontal EE

     $FFFF82A0 (word) : VFC - Vertical Frequency Counter
     $FFFF82A2 (word) : VFT - Vertical Frequency Timer
     $FFFF82A4 (word) : VBB - Vertical Border Begin
     $FFFF82A6 (word) : VBE - Vertical Border End
     $FFFF82A8 (word) : VDB - Vertical Display Begin
     $FFFF82AA (word) : VDE - Vertical Display End
     $FFFF82AC (word) : VSS - Vertical SS

I know I can change the palette at any time in the screen (raster 
effect), but can I have a upper screen in overscan and a lower screen 
with borders for example ?



Le 05/02/2011 21:45, Matthias Arndt a écrit :
> Am Samstag, den 05.02.2011, 13:18 +0100 schrieb Nicolas Pomarède:
>> Well, I think we agree then ; my point is exactly "let's forget how the
>> shifter works in STF/STE mode, don't reuse the code of video.c in
>> videl.c" (we'll see later if some program still don't work in STE mode
>> under falcon)
> Yep, i definitly agree. It is the Videl to be emulated with all its
> special features and bugs and not the Shifter, even if some operational
> modes are similar.
> cheers,
> Matthias

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