Difference between revisions of "OSBYTE &71"

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OSBYTE &71 (113) - Select Main/Shadow for Display hardware
 
OSBYTE &71 (113) - Select Main/Shadow for Display hardware
  
        X=0 Use whatever the default for the current mode is
+
    Y=0 X=as per OSByte &70
        X=1 Use main memory
+
     The value of X defines which bank the hardware will output
        X=2 Use shadow memory
 
    (Risc OS 1.00)
 
     The value of X can be greater than 2 as well, and instructs the video
 
    hardware to use the bank at screenbase+(X*modesize)
 
 
 
This call specifies which bank of memory the Master video display hardware
 
access. Using this and [[OSBYTE &70]] a program can use the VDU to write to
 
one bank of memory while the other is being displayed.
 
  
 
==See Also==
 
==See Also==
* [[OSBYTE &6C]] - Select Master shadow memory
 
* [[OSBYTE &6F]] - Select BBC B shadow memory
 
* [[OSBYTE &70]] - Select memory for Master VDU access
 
* [[OSBYTE &71]] - Select memory for Master video display
 
* [[OSBYTE &72]] - Select future use of shadow memory
 
* [[OSBYTE &73]] - Select shadow bank
 
* [[OSBYTE &74]] - Check for Solidisk shadow memory
 
* [[Paging in video memory]]
 
 
* http://mdfs.net/Docs/Comp/BBC/Osbyte00
 
* http://mdfs.net/Docs/Comp/BBC/Osbyte00
  
[[User:WikiSysop|WikiSysop]] 00:24, 29 August 2013 (BST)
+
[[User:Jgharston|Jgharston]] 21:46, 26 May 2009 (UTC)

Revision as of 01:13, 8 March 2015

OSBYTE &71 (113) - Select Main/Shadow for Display hardware

   Y=0 X=as per OSByte &70
   The value of X defines which bank the hardware will output

See Also

Jgharston 21:46, 26 May 2009 (UTC)