Difference between revisions of "OSBYTE &6C"

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[[Category:OSBYTE]]
 
[[Category:OSBYTE]]
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OSBYTE &6C (108) - Main/Shadow RAM access
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OSBYTE &6C (108) - Main/Shadow RAM Usage
  
 
     Y=0 X=0 Main memory appears from &3000 to &7FFF
 
     Y=0 X=0 Main memory appears from &3000 to &7FFF
 
         X=1 Shadow memory appears from &3000 to &7FFF
 
         X=1 Shadow memory appears from &3000 to &7FFF
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    This has immediate effect and allows the user to make use of the 20k of
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This has immediate effect and allows the user to access the Master's 20K
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    extra RAM for other purposes.
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shadow RAM, for instance, to load or save it or manipulate it directly. The
 
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memory that is accessed by the VDU drives and displayed can set with
 
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[[OSBYTE &70]] and [[OSBYTE &71]].
 
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On the BBC B+ the displayed memory is always the bank selected with MODE or
 
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[[OSBYTE &72]], and the user can only access the shadow memory by calling
 
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[[OSRDSC]].
 
  
 
==See Also==
 
==See Also==
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* [[OSBYTE &6C]] - Select Master shadow memory
 
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* [[OSBYTE &6F]] - Select BBC B shadow memory
 
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* [[OSBYTE &70]] - Select memory for Master VDU access
 
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* [[OSBYTE &71]] - Select memory for Master video display
 
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* [[OSBYTE &72]] - Select future use of shadow memory
 
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* [[OSBYTE &73]] - Select shadow bank
 
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* [[OSBYTE &74]] - Check for Solidisk shadow memory
 
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* [[Paging in video memory]]
 
 
* http://mdfs.net/Docs/Comp/BBC/Osbyte00
 
* http://mdfs.net/Docs/Comp/BBC/Osbyte00
  
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[[User:WikiSysop|WikiSysop]] 00:21, 29 August 2013 (BST)
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[[User:Jgharston|Jgharston]] 21:15, 26 May 2009 (UTC)

Revision as of 02:13, 8 March 2015

OSBYTE &6C (108) - Main/Shadow RAM Usage 

   Y=0 X=0 Main memory appears from &3000 to &7FFF
       X=1 Shadow memory appears from &3000 to &7FFF
   This has immediate effect and allows the user to make use of the 20k of
   extra RAM for other purposes.

See Also

Jgharston 21:15, 26 May 2009 (UTC)

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