( 39 new-vlank process                    )› decimal›: TASK:  creat [compile] assembler›  assembler mem ( switch now  )›  here    ( save pfa )›  0 scan-tasks  ( find entry now  )›  !csp›  mtoff ;›: ;TASK current @ context !›  ?csp  ( everything secure )›  !  ( store pfa into table entry )›  mton  ; ( do multi-tasking )›: INSTALL›  [compile]  0 scan-tasks›   sneak  ; ( the change into table )›: REMOVE  [compile]  scan-tasks›  0 swap sneak ; ( delete by nulling )››( 41 trying a blinking task                        )› hex›0 variable time-left›0 variable rate›0 variable blank-state›d401 constant chactl  ( char control )› task: blink› time-left  lda, 0=›  if, blank-state lda, 0= NOT›      if, 0 # lda,›      else, 1 # lda,›      then,›     chactl sta, blank-state sta,›     rate lda, time-left sta,›   else, time-left drc,›   then, rts,› ;tasks››( 42 sound handler example                           )› hex›label envelope›a0 c, a1 c, a2 c, 00 c, a5 c, a6 c,›a8 c, 00 c, ab c, ac c, 00 c, af c,›c variable into›0 variable sounding›0 variable old.key› decimal››( 43 sound handler example                           )› hex›0 voice› task: key.noise›  sounding lda, 0= not›       if, into ldx,›           envelope ,x lda, audv sta,›           volume sta›           dex, 0<›         if, 0 # lda, sounding sta,›          c # ldx, then, into stx,›       else, d209 lda, old.key cmp, 0= not›        if, audf sta, old.key sta,›            1 # lda, sounding sta,›       then,›      then, rts,›;task›decimal››( 35 new vblank vectors                          )› HEX›e45c  constant SETVBV›e460  constant VBLANKI›e463  constant VBLANKD ( OS dependant )›code Set-Vblankd ( addr is on stack )›  pha, tya, pha, xsave stx,›  bot lda, pha,  ( IS ON STACK )›  bot 1+ lda, tax, pla, tay,›  7 # lda, setvbv jsr,›  pla, tay, pla, xsave ldx,›  pop jmp,›end-code› decimal›( the 7 # lda, would be changed to 6 )›( for the immediate vblankd vector)›( and to 1-5 for timers 1-5 )››( 36 setting up task table                                )›00 variable TASK#›00 variable JUMPER ( indirect jump )› label TASK-TABLE›00 , 00 , 00 , 00 , 00 , 00 , 00 , 00 ,››( 37 setting up task table                               )›code WHOSE-TURN›      task# lda, .a asl, tax,›      task-table 1+ ,x lda, 0= not›      if, jumper 1+ sta, ( install pointer)›         task-table ,x lda, jumper sta,›         jumper ) jmp,›      then, rts,›end-code›code NEXT-TASK  clc, task# lda,›     1 # adc, 03 # and, task# sta, rts,›end-code›( 4 entries in a table are checked )›code NEW-VBLANK›     whose-turn jsr›     next-task    jsr,›    vblankd        jmp, end-code›decimal››( 38 new-vblank process                                   )› decimal›: SCAN-TASKS ( match val)›   -1 swap 32 0 ( flag for 0<)›   do i task-table + dup ( addr in tabl)›      @ 3 pick =  ( match to given val )›      if rot drop. ( loose 0< flag)›         swap leave›      else drop  ( addr or flag )›      then›   2 +loop drop  ( given val )›   dup 0< 44 ?error   ;›( task table in lower 32k of memory !! )›: MTOFF  vblankd set-vblankd  ;›( disable and enable multi-tasking     )›: MTON   new-vblank set-vblankd  ;›: SNEAK  mtoff !  mton  ;›( synchronized storage                      )›