The microprocessor 18 handles the interface to {TAIL ~ the controller} 20, {HEAD ~ the channel interface} 16 and the RAM 12, as well as determining when to read/write the video in the RAM to/from the disk drive 14 
The microprocessor 18 handles the interface to { TAIL ~ the controller } 20 , { HEAD ~ the channel interface } 16 and the RAM 12 , as well as determining when to read / write the video in the RAM to / from the disk drive 14
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH