Difference between revisions of "OSBYTE &16"

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     calls (type &15) per second to be sent the paged ROMs. This allows a way  
 
     calls (type &15) per second to be sent the paged ROMs. This allows a way  
 
     for ROMs to poll hardware which doesn't offer interrupts.
 
     for ROMs to poll hardware which doesn't offer interrupts.
 +
   
 +
    On exit:
 +
      X=preserved - Polling semaphore exists
 +
      X=&FF      - Polling semaphore not implemented
  
 
==See Also==
 
==See Also==
 +
* [[OSBYTE &17]] - Decrement Polling Semaphore
 
* http://mdfs.net/Docs/Comp/BBC/Osbyte00
 
* http://mdfs.net/Docs/Comp/BBC/Osbyte00
  
 
[[User:Jgharston|Jgharston]] 21:31, 26 May 2009 (UTC)
 
[[User:Jgharston|Jgharston]] 21:31, 26 May 2009 (UTC)
 +
[[User:Jgharston|Jgharston]] ([[User talk:Jgharston|talk]]) 02:03, 6 November 2020 (CET)

Latest revision as of 02:03, 6 November 2020

OSBYTE &16 (22) - Increment Polling Semaphore

   This call increments a counter, which if non zero will cause 100 service
   calls (type &15) per second to be sent the paged ROMs. This allows a way 
   for ROMs to poll hardware which doesn't offer interrupts.
   
   On exit:
     X=preserved - Polling semaphore exists
     X=&FF       - Polling semaphore not implemented

See Also

Jgharston 21:31, 26 May 2009 (UTC) Jgharston (talk) 02:03, 6 November 2020 (CET)