Difference between revisions of "OSBYTE &72"

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m (moved OSBYTE 72 to OSBYTE &72)
 
m (Added return value.)
 
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[[Category:OSBYTE]]
 
[[Category:OSBYTE]]
OSBYTE &72 (114) - Write to Shadow/Main toggle
+
OSBYTE &72 (114) - Specify video memory to use on next MODE change
  
         X=0 force use of shadow memory on future mode changes
+
    On entry:
         X=1 only use shadow memory if mode number is > 127
+
         X=0 force use of shadow memory on future MODE changes
     (Solidisk ROM/RAM Extension)
+
         X=1 only use shadow memory if MODE number is > 127
         X=255 never use shadow memory
+
     Solidisk ROM/RAM Extension:
 +
         X=255 never use shadow memory even if MODE > 127
 +
    On exit:
 +
        X=previous setting
  
==See Also==
+
This OSBYTE is called by the '''*SHADOW''' command.
 +
 
 +
==See also==
 +
* [[OSBYTE &49]] - Check for Integra-B shadow memory
 +
* [[OSBYTE &6C]] - Select Master/Integra-B 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:Jgharston|Jgharston]] 21:51, 26 May 2009 (UTC)
+
[[User:Jgharston|Jgharston]] ([[User talk:Jgharston|talk]]) 01:13, 4 April 2015 (UTC)

Latest revision as of 03:13, 4 April 2015

OSBYTE &72 (114) - Specify video memory to use on next MODE change

   On entry:
       X=0 force use of shadow memory on future MODE changes
       X=1 only use shadow memory if MODE number is > 127
   Solidisk ROM/RAM Extension:
       X=255 never use shadow memory even if MODE > 127
   On exit:
       X=previous setting

This OSBYTE is called by the *SHADOW command.

See also

Jgharston (talk) 01:13, 4 April 2015 (UTC)