Difference between revisions of "OSBYTE &8F"

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(Specification: added table)
(presence of result not contingent on claim; preservation of Y relies on ROMs cooperating)
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| X || align="left" | Service request code || align="left" | =0 service call claimed<br>&lt;&gt;0 service call not claimed
 
| X || align="left" | Service request code || align="left" | =0 service call claimed<br>&lt;&gt;0 service call not claimed
 
|- align="center" valign="top"
 
|- align="center" valign="top"
| Y || align="left" | Parameter to service call || align="left" | Result from service call if claimed<br>Preserved if service call not claimed
+
| Y || align="left" | Parameter to service call || align="left" | Result from service call
 
|}
 
|}
 +
 +
;Note
 +
Certain [[service calls]] such as &01 and &02 return a result in Y without claiming the call.<br>
 +
Other unclaimed calls preserve Y, provided that all paged ROMs behave correctly.
  
 
==See Also==
 
==See Also==

Revision as of 19:56, 11 December 2021

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)