RobotStudio event

why string length is limited to 80 characters in RAPID

edited November 2014 in Robot Controller

It is described in the RAPID reference manual that, "a character string consists of a number of characters ( a maximum of 80) enclosed by quotation marks". 

My questions is, why to limit the string length to 80 characters in RAPID? Does there have some historical reasons? 

If this limit comes from the limit of memory / CPU at the time when RAPID was invented, then this limit could be removed for modem designed Robot Controller, isn't it? 

Looking forward to the reply, 



  • String length would be limited by the amount of memory assigned to the variable when created. 
  • 80 characters length is a heavy limit to a string for some applications communicate with external devices by networking.

    1 character takes 8 bytes, then 80 characters just take 640 bytes. 

    The amount of the limited memory is not a good reason for the nowadays's RAC...
  • <p>A string isn't a data type in the same sense as an integer or character.  It's actually a class.  So when I say the amount of memory assigned, it is whoever designed the string class, how much memory/number of characters they decided to allow.  So what you say about memory not being very limited is right, but for whatever reason the person who developed the string class had, they decided 80 was the limit.</p>
  • Does anyone know about a workaround to use longer strings? Some other data type?
  • I have the same issue. Is there a work around? Will this be changed in future controller versions?
  • soup
    soup ✭✭✭
    edited February 2019
    I'm up for thinking -- but need the specific case to be relevant to your application. I've "worked around" string size by using an array of strings, but it was probably a much simpler issue than what you're dealing with...