IF... THEN... ELSE syntax help needed.

Comments

• erco Posts: 20,261

  2012-02-16 09:28 edited 2012-02-16 09:28

  Looks good. You are using PBASIC 2.5, not 2.0?
• searthur Posts: 8

  2012-02-16 09:34 edited 2012-02-16 09:34

  I'm running 2.5.2 When I do a syntax check I get "expected ":" or end-of-line error just after the IN6=0. So is it ok to have more than one ELSEIF like I'm trying to do above?
• erco Posts: 20,261

  2012-02-16 09:56 edited 2012-02-16 09:56

  IF IN6=0
  
  IF IN7=1
  
  You left out two IF statements.
• Ron Czapala Posts: 2,418

  2012-02-16 10:02 edited 2012-02-16 10:02

  I generally avoid ELSEIF, but try:
  

  ' {$STAMP BS2}
  ' {$PBASIC 2.5}
  Main:
  IF (IN5=0) THEN
    GOTO GPOHI
  ELSEIF(IN6=0) THEN
    GOTO GPOHI
  ELSEIF (IN7=1) THEN
    GOTO GPOHI
  ELSE
    GOTO GPOLO
  ENDIF
  GOTO Main
  END
  
  GPOHI:
   HIGH 15 'Energize relay 1
   HIGH 14 'Energize relay 2
   HIGH 13 'Energize relay 3
   GOTO Main
  
  GPOLO:
   LOW 15 'Relax relay 1
   LOW 14 'Relax relay 2
   LOW 13 'Relax relay 3
   GOTO Main
  
• erco Posts: 20,261

  2012-02-16 10:14 edited 2012-02-16 10:14

  Main:
  IF IN5=0 THEN GPOHI
  IF IN6=0 THEN GPOHI
  IF IN7=1 THEN GPOHI
  GOTO GPOLO
  
  or:
  
  Main:
  IF IN5=0 OR IN6=0 OR IN7=1 THEN GPOHI
  GOTO GPOLO
• Tracy Allen Posts: 6,667

  2012-02-16 10:15 edited 2012-02-16 10:15

  That particular condition could be written
  

  IF IN5=0 OR IN6=0 OR IN7=1 THEN GOTO GPOHI ELSE GOTO GPOLO
  
• searthur Posts: 8

  2012-02-16 10:16 edited 2012-02-16 10:16

  I get "label already defined" at the second ELSEIF...
• searthur Posts: 8

  2012-02-16 10:19 edited 2012-02-16 10:19

  I get "expected a label" after the "THEN" statement.
• searthur Posts: 8

  2012-02-16 10:22 edited 2012-02-16 10:22

  What about this (see below). It passes the syntax check and I think will do the same thing.
  
  Main:
  IF IN5=0 THEN GPOHI
  IF IN6=0 THEN GPOHI
  IF IN7=1 THEN GPOHI
  GOSUB GPOLO
  GOTO Main
  END
  
  '******************************************************************[ Subroutines ]
  '
  GPOHI:
  HIGH 15 'Energize relay 1
  HIGH 14 'Energize relay 2
  HIGH 13 'Energize relay 3
  GOTO Main
  
  GPOLO:
  LOW 15 'Relax relay 1
  LOW 14 'Relax relay 2
  LOW 13 'Relax relay 3
  RETURN
  GOTO Main
• erco Posts: 20,261

  2012-02-16 10:27 edited 2012-02-16 10:27

  Sure, that subroutine works, too. You don't need your END or final GOTO MAIN statement, as they'll never execute.
• Ron Czapala Posts: 2,418

  2012-02-16 10:34 edited 2012-02-16 10:34

  Make sure you have the
  
  ' {$PBASIC 2.5}
  
  statement if you want to use 2.5
• searthur Posts: 8

  2012-02-16 10:35 edited 2012-02-16 10:35

  Thanks erco. This seems to work nicely (see below).
  
  Main:
  IF IN5=0 OR IN6=0 OR IN7=1 THEN GPOHI
  GOTO GPOLO
  
  
  
  GPOHI:
  HIGH 15 'Energize relay 1
  HIGH 14 'Energize relay 2
  HIGH 13 'Energize relay 3
  GOTO Main
  
  GPOLO:
  LOW 15 'Relax relay 1
  LOW 14 'Relax relay 2
  LOW 13 'Relax relay 3
  GOTO Main
• searthur Posts: 8

  2012-02-16 10:37 edited 2012-02-16 10:37

  Thank you everyone for all the assistance. I really appreciate it.