From BeebWiki
Jump to: navigation, search

OSBYTE &73 (115) - Select shadow RAM bank used

   On entry:
       X=0 Shadow bank 8
       X=1 Shadow bank 9
   Electron OS:
   Blank/restore palette
   On entry:
       X=0  restores the palette, on exit X=0
       X<>0 sets the whole palette to black if in high resolution mode
            on exit, X<4

Software using NMIs in high resolution screen modes can prevent snow appearing on the screen during NMIs (due to ULA reuse) by blanking the palette.

See also

Jgharston 21:52, 26 May 2009 (UTC) Jgharston (talk) 20:32, 3 April 2015 (UTC)