OSBYTE &8F

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Revision as of 20:56, 11 December 2021 by Regregex (talk | contribs) (presence of result not contingent on claim; preservation of Y relies on ROMs cooperating)
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OSBYTE &8F (143) - Issue SWR Service Request (on exit Y=response to request if appropriate)

   X=request number
   Y=parameter to pass (varies depending on the request number)

Specification

 6502  On entry: On exit:
A =&8F preserved
X Service request code =0 service call claimed
<>0 service call not claimed
Y Parameter to service call Result from service call
Note

Certain service calls such as &01 and &02 return a result in Y without claiming the call.
Other unclaimed calls preserve Y, provided that all paged ROMs behave correctly.

See Also

Jgharston 21:26, 26 May 2009 (UTC)