Why is this code not working?

Comments

• ericball Posts: 774

  2011-07-04 17:38 edited 2011-07-04 17:38

  I don't program in SPIN much, but I know that all parameters and return values in SPIN are LONGs. You attempt to be returning a string.
• Mike Green Posts: 23,101

  2011-07-04 17:49 edited 2011-07-04 17:49

  It seems like it ought to be possible to specify word values with strings with two characters or long values with strings with three or four characters, but it doesn't work that way. You can write "W" << 8 | "S" if you want the first character in bits 15-8. For three characters, you might use ("W" << 16) | ("N" << 8) | "N". If you want the characters in some other order, you can specify that any way you want.
• JonnyMac Posts: 9,554

  2011-07-04 18:17 edited 2011-07-04 18:17

  I've attached a possible solution. It uses a DAT table of strings and modifies your routine to point into it.

  spin

  spin

  jm_compass.spin

  4K

  jm_compass.spin 3.6K
• Unsoundcode Posts: 1,532

  2011-07-04 18:28 edited 2011-07-04 18:28

  Similar to JohnnyMac's , pointers to strings
  

  case  degrees
        0..11   : Heading :=@N     
        12..34  : Heading :=@NNE 
        35..56  : Heading :=@NE
        
  debug.str(Heading) 
   
  dat
   N   byte "N",0
   NNE byte "NNE",0    
   NE  byte "NE",0
  
  

  
  Jeff T.
• Franklin Posts: 4,747

  2011-07-04 18:52 edited 2011-07-04 18:52

  Thanks guys, I'll look those over as I probably should be using dat statements anyway. Here is what I have now and it works.

  PUB convertHeading (degrees) 
      case  degrees
        0..11   : Heading := "N"
        12..34  : Heading := ("E"<<16)|("N"<<8)|"N"
        35..56  : Heading := ("N"<<8)|"E"
        57..79  : Heading := ("E"<<16)|("N"<<8)|"E"
        80..101 : Heading := "E"
        102..124: Heading := ("E"<<16)|("S"<<8)|"E"
        125..146: Heading := ("S"<<8)|"E"
        147..169: Heading := ("E"<<16)|("S"<<8)|"S"
        170..191: Heading := "S"
        192..214: Heading := ("W"<<16)|("S"<<8)|"S"
        215..236: Heading := ("S"<<8)|"W"
        237..259: Heading := ("W"<<16)|("S"<<8)|"W"
        260..281: Heading := "W"
        282..304: Heading := ("W"<<16)|("N"<<8)|"W"
        305..326: Heading := ("N"<<8)|"W"
        327..348: Heading := ("W"<<16)|("N"<<8)|"N"
        348..360: Heading := "N"
  

  and it is called like this.

  convertHeading(value)
    term.str(@Heading)
  
• Franklin Posts: 4,747

  2011-07-04 19:03 edited 2011-07-04 19:03

  Jon, your code always fascinates me. I have to read it several times to figure out what it all does (rjdec) that's just elegant (or at least freaky)
• Cluso99 Posts: 18,071

  2011-07-04 19:23 edited 2011-07-04 19:23

  Franklin: You code posted in #6 is a little cumbersome. However, if you define heading in the same way as you did in the case statement in #1, but instead of passing the result returned in Heading, you use Heading as a global varaible, that will work. Essentially that is what you have done in the end but it just is cleaner and is terminated with the required null.
• JonnyMac Posts: 9,554

  2011-07-04 20:23 edited 2011-07-04 20:23

  Jon, your code always fascinates me.

  
  While I like to write my own code, when I find something really elegant and useful I will snatch it up and put it to use -- such is the case with the rjdec() methd. That code (if under a different method name), I believe, was written by Dave Hein.