Why is it that the RL02 disk system of the PDP11 has a seek command yet the read command also knows where to read from as the cylinder/head/sector are given via the 'DAR' register? http://www.bitsavers.org/www.computer.museum.uq.edu.au/pdf/EK-RL012-UG-005%20RL01-RL02%20User%20Guide.pdf page 4-13