Difference between revisions of "OSBYTE &CA"

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(Tested and rewritten to clarify action.)
(Added Compact EXTEND key status.)
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   This byte determines the current state of the keyboard modifier keys
 
   This byte determines the current state of the keyboard modifier keys
     b0 = BBC/Electron: reserved             RISC OS: Alt pressed
+
     b0 = BBC/Electron: reserved   Compact: b0-b2 = EXTEND status            RISC OS: Alt pressed
     b1 = BBC/Electron: reserved             RISC OS: Scroll Lock set
+
     b1 = BBC/Electron: reserved               1=EXTEND, 2=Shift-EXTEND        RISC OS: Scroll Lock set
     b2 = BBC/Electron: reserved             RISC OS: Num Lock set
+
     b2 = BBC/Electron: reserved               3=Ctrl-EXTEND, 4=Sh-Ct-EXTEND  RISC OS: Num Lock set
 
     b3 = Shift pressed
 
     b3 = Shift pressed
 
     b4 = Caps lock off
 
     b4 = Caps lock off
 
     b5 = Shift lock off
 
     b5 = Shift lock off
 
         (ie, b5-4=01: Shift Lock on, 10: Caps Lock on, 11: No lock)
 
         (ie, b5-4=01: Shift Lock on, 10: Caps Lock on, 11: No lock)
     b6 = Electron: FN pressed            BBC/RISC OS: Control pressed
+
     b6 = BBC/RISC OS: Control pressed        Electron: FN pressed
 
     b7 = Shift enable (Shift Caps or Shift Inverse)
 
     b7 = Shift enable (Shift Caps or Shift Inverse)
 
    
 
    

Revision as of 14:36, 25 March 2018

OSBYTE &CA (202) - Read/Write Keyboard Status

 This byte determines the current state of the keyboard modifier keys
   b0 = BBC/Electron: reserved    Compact: b0-b2 = EXTEND status             RISC OS: Alt pressed
   b1 = BBC/Electron: reserved               1=EXTEND, 2=Shift-EXTEND        RISC OS: Scroll Lock set
   b2 = BBC/Electron: reserved               3=Ctrl-EXTEND, 4=Sh-Ct-EXTEND   RISC OS: Num Lock set
   b3 = Shift pressed
   b4 = Caps lock off
   b5 = Shift lock off
       (ie, b5-4=01: Shift Lock on, 10: Caps Lock on, 11: No lock)
   b6 = BBC/RISC OS: Control pressed         Electron: FN pressed
   b7 = Shift enable (Shift Caps or Shift Inverse)
 
 With Caps Lock on and Shift Enable off, Shift has no effect on letter keys.

Examples

  • *FX 202,16 turns Shift Lock on
  • *FX 202,32 turns Caps Lock on
  • *FX 202,48 turns Caps Lock/Shift Lock off
  • *FX 202,160 turns Shift Caps on


Jgharston 22:48, 26 May 2009 (UTC) Jgharston (talk) 20:18, 13 June 2016 (UTC)