******* trackdisk.device/TD_XX *******************************************
*
*   NAME
*	TD_XX - get the current key map structure for this console
*
*   FUNCTION
*	Fill the IO_DATA buffer with the current KeyMap structure in
*	use by this console unit.
*
*   IO REQUEST
*	io_Command	TD_XX, ETD_XX
*	io_Offset	logical offset from beginning of disk (in bytes).
*			  Must be in multiples of TD_SECTOR.
*	io_Length	length of user's buffer in bytes.  Must be in
*			  multiples of TD_SECTOR.
*	io_Data		pointer to buffer in chip memory.
*	tdio_Count	(extended version only) set to maximum change
*			  counter value allowable for this call.
*	tdio_SecLabel	(extended version only) pointer to buffer to
*			  hold sector label array, or NULL if not wanted.
*
*   RESULTS
*	io_Actual	number of bytes actually read into the user's
*			  buffer
*
*   SEE ALSO
*	TD_XX
*
**************************************************************************
