Difference between revisions of "OSBYTE &9B"

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(Write to VULA, not to 6845.)
 
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OSBYTE &9B (155) - Write to Video ULA palette register and RAM copy
 
OSBYTE &9B (155) - Write to Video ULA palette register and RAM copy
  
     This call places X into register 1 of the 6845, and updates the RAM copy
+
     This call writes X to the Video ULA palette register and updates
     (Electron OS only)
+
    the RAM copy. The RAM copy is of little use as there are 16 entries
 +
    in the Video ULA palette and the RAM copy will only hold the last
 +
    value written to it. The RAM copy of the palette is in the VDU
 +
    workspace at &035F-&037E.
 +
 
 +
     Electron OS:
 
     Completely ignored, performing an RTS immediately
 
     Completely ignored, performing an RTS immediately
  
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[[User:Jgharston|Jgharston]] 22:11, 26 May 2009 (UTC)
 
[[User:Jgharston|Jgharston]] 22:11, 26 May 2009 (UTC)
 +
[[User:Jgharston|Jgharston]] ([[User talk:Jgharston|talk]]) 07:44, 30 November 2016 (UTC)

Latest revision as of 08:44, 30 November 2016

OSBYTE &9B (155) - Write to Video ULA palette register and RAM copy

   This call writes X to the Video ULA palette register and updates
   the RAM copy. The RAM copy is of little use as there are 16 entries
   in the Video ULA palette and the RAM copy will only hold the last
   value written to it. The RAM copy of the palette is in the VDU
   workspace at &035F-&037E.
   Electron OS:
   Completely ignored, performing an RTS immediately

See Also

Jgharston 22:11, 26 May 2009 (UTC) Jgharston (talk) 07:44, 30 November 2016 (UTC)