' =========================================================================
'
'   File....... TaskManager.BS2
'   Purpose....
'   Author..... Jon Williams -- Parallax, Inc.
'   E-mail..... jwilliams@parallax.com
'   Started....
'   Updated.... DD MMM YYYY
'
'   {$STAMP BS2}
'   {$PBASIC 2.5}
'
' =========================================================================


' -----[ Program Description ]---------------------------------------------


' -----[ Revision History ]------------------------------------------------


' -----[ I/O Definitions ]-------------------------------------------------


' -----[ Constants ]-------------------------------------------------------

Task0           CON     0
Task1           CON     1
Task2           CON     2

LastTask        CON     2


' -----[ Variables ]-------------------------------------------------------

taskCtrl        VAR     Nib


' -----[ EEPROM Data ]-----------------------------------------------------


' -----[ Initialization ]--------------------------------------------------

Reset:


' -----[ Program Code ]----------------------------------------------------

Main:
  DO
    GOSUB Critical_Task
    ON taskCtrl GOSUB Do_Task0, Do_Task1, Do_Task1
    IF (taskCtrl > LastTask) THEN               ' trap error
      taskCtrl = Task0
    ENDIF
  LOOP
  END


' -----[ Subroutines ]-----------------------------------------------------

Critical_Task:

  ' software "interrupt" code here

  RETURN


' -------------------------------------------------------------------------

Do_Task0:

  ' task 0 code

  taskCtrl = Task1                              ' point to next task
  RETURN


' -------------------------------------------------------------------------

Do_Task1:

  ' task 1 code

  taskCtrl = Task2
  RETURN


' -------------------------------------------------------------------------

Do_Task2:

  ' task 2 code

  IF (condition) THEN                           ' conditionally select
    taskCtrl = Task0                            '   next task
  ELSE
    taskCtrl = Task3
  ENDIF
  RETURN 