                                        1 sub1 soap tape library   
                                        1      routine 
                                        1                   
                                        0 sub1 nop 0000       comment
                                        0      hlt 0001
                                        1
                                               ?
                                          sub2 nop 0002       comment
                                        0      hlt 0002
                                        1
                                               ?
                                               ?
