DEVICE HANDLER                      RESIDENT MONITOR


          +-----------------------------+
          |      PREAMBLE SECTION       |
          +-----------------------------+
          |       HEADER SECTION        |       PUTS NEW QUEUE ELEMENT ON THIS
          +-----------------------------+       HANDLER'S QUEUE AND CALLS THE
          |   I/O INITIATION SECTION <--------- HANDLER AS A CO-ROUTINE.
          |             .               |
          |             .               |
DEVICE    |          RTS PC ------------------> RUNS THIS JOB, OR WAITS FOR
INTERRUPT +-----------------------------+       THIS TRANSFER TO COMPLETE.
------------> INTERRUPT SERVICE SECTION |
          |             .               |
          |             .               |
          |             .               |
          +-----------------------------+
          |   I/O COMPLETION SECTION    |
          |             .               |
          |             .               |
          |             .               |
          |          .DRFIN ------------------> RETURNS QUEUE ELEMENT TO THE
          +-----------------------------+       LIST OF AVAILABLE ELEMENTS, OR
          | HANDLER TERMINATION SECTION |       PUTS IT ON THE COMPLETION QUEUE.
          +-----------------------------+