OSBYTE &75

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OSBYTE &75 (117) - Read VDU Status Byte

   On exit:
   X=b0 Print output enabled by VDU2
     b1 Scrolling disabled
     b2 Paged scrolling selected by VDU14
     b3 Text window in force, ie software scrolling
     b4 In a shadow mode on Master
     b5 In VDU5 mode
     b6 Cursor editing in progress
     b7 Screen disabled with VDU21

Note, bit 4 is only set by shadow screen modes on the Master series and the BBC B+. With shadow screen systems on the BBC B and Electron a different flag is used.

See also

Jgharston 21:53, 26 May 2009 (UTC) Jgharston (talk) 20:33, 3 April 2015 (UTC)