OSBYTE &FE

OSBYTE &FE (254) - Read/Write available RAM

   These bits refer to 16K/32K machine:
   When read &40=16K
             &80=32K
   (Electron OS)
   This value returns 0 and is otherwise undefined
   (Acorn MOS 2.00)
   This value returns 1 and is otherwise undefined
   (Acorn MOS 3.20)
   Read/Write effect of shift on Numeric pad
   A zero in this location makes SHIFT-keypad presses act like their main
   keyboard counterparts.A non zero value means shift is ignored.
   (RISC OS 1.00)
   A zero in this location enables both SHIFT and CTRL-keypad presses:
   For keys 128 and above (ie.the base has been altered with OSByte 238)
      CTRL-keypad gives keypad key EOR&20
      SHIFT-keypad gives keypad key EOR&10
   For keys below 128
      CTRL and SHIFT are ignored

See Also

• http://mdfs.net/Docs/Comp/BBC/OsbyteA6

Jgharston 23:21, 26 May 2009 (UTC)