OSBYTE &FF

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OSBYTE &FF (255) - Read/Write startup Options

   This is a copy of the keyboard links taken at last hard reset
   b0..2=screen mode
   b3   =if clear then the action of SHIFT/BREAK is reversed
   b4..5=disk drive speed        step time  settle time  head load
               b5=0  b4=0            4ms        16ms         0ms
               b5=0  b4=1            6ms        16ms         0ms
               b5=1  b4=0            6ms        50ms         32ms
               b5=1  b4=1            24ms       20ms         64ms
   b6   =HADFS:  0=drive 1 external, 1=drive 1 internal, via OSWORD &7F
   b6   =ENFS:   0=unPROTed on Break, 1=PROTed on Break
   b7   =DNFS:   0=NFS priority, 1=DFS priority
   b7   =ENFS:   0=use buffered I/O and raise PAGE by &100, 1=don't use buffered I/O
   b7   =Master: screen mode b7

See Also

WikiSysop (talk) 13:36, 8 March 2015 (UTC)