Difference between revisions of "OSWORD &FC"

From BeebWiki
Jump to: navigation, search
m (1 revision)
(Rewrote transaction description.)
Line 1: Line 1:
−
[[Category:OSWORD]]
+
[[Category:OSWORD]][[Category:Second Processors]]__NOTOC__
−
OSWORD &FC (252) - DOS CRTC Control 80x86 DOS
+
{{PageTitle|OSWORD &FC (252) DOS CRTC Control}}
 +
This OSWORD call is installed by the 80x86 DOS BIOS.
  
−
The control block is ignored, so for speed, set XY?0=0 and XY?1=0.
+
Commands are sent from the 80x86 via Tube Register 2 within the OSWORD protocol,
−
Commands are sent from the 80x86 via Tube register 2:
+
so cannot be called through the normal OSWORD mechanism. The transaction must be
−
b7=0 - program CRTC, command specifies register, next byte sent
+
done manually by the client by sending through Tube Register 2:
−
    through register 2 is the CRTC data.
+
    &08 : Start OSWORD transaction
−
&FC - write to mouse port (does nothing)
+
    &FD : OSWORD call &FD
−
&FD - intercept events
+
    &00 : TxLen=0
−
&FE - initialise mouse driver
+
    xxx : Send a series of commands
−
&FF - finish. All other commands finish the transaction.
+
    &00 : RxLen=0, terminate the OSWORD call
  
−
==See Also==
+
===Commands===
−
* http://mdfs.net/Docs/Comp/BBC/Oswords
+
* b7=0 : program CRTC, command specifies register, next byte sent is the CRTC data
 +
* &FC : write to mouse port (unimplemented)
 +
* &FD : initialise event handler
 +
* &FE : initialise mouse driver
 +
* &FF : finish. All other commands also finish the transaction.
 +
 
 +
==See also==
 +
* [[OSWORD &FA]]
 +
* [[OSWORD &FB]]
 +
* [[OSWORD &FD]]
 +
* [[OSWORD &FE]]
 +
* [[OSWORD &FF]]
 +
* [http://mdfs.net/Software/Tube/Utils/ OSWORD &FC source code]
 +
* [http://mdfs.net/Docs/Comp/BBC/Oswords OSWORDs list at mdfs.net]
  
 
[[User:Jgharston|Jgharston]] 14:28, 26 May 2009 (UTC)
 
[[User:Jgharston|Jgharston]] 14:28, 26 May 2009 (UTC)
 +
[[User:Jgharston|Jgharston]] ([[User talk:Jgharston|talk]]) 10:55, 17 December 2024 (CET)

Revision as of 10:55, 17 December 2024

OSWORD &FC (252) DOS CRTC Control

This OSWORD call is installed by the 80x86 DOS BIOS.

Commands are sent from the 80x86 via Tube Register 2 within the OSWORD protocol, so cannot be called through the normal OSWORD mechanism. The transaction must be done manually by the client by sending through Tube Register 2: 

   &08 : Start OSWORD transaction
   &FD : OSWORD call &FD
   &00 : TxLen=0
   xxx : Send a series of commands
   &00 : RxLen=0, terminate the OSWORD call

Commands

  • b7=0 : program CRTC, command specifies register, next byte sent is the CRTC data
  • &FC : write to mouse port (unimplemented)
  • &FD : initialise event handler
  • &FE : initialise mouse driver
  • &FF : finish. All other commands also finish the transaction.

See also

Jgharston 14:28, 26 May 2009 (UTC) Jgharston (talk) 10:55, 17 December 2024 (CET)

Retrieved from "http://beebwiki.mdfs.net/index.php?title=OSWORD_%26FC&oldid=4756"