Using strings

dk_akj · 2004-08-05 19:47

Hi.

Just received my first stamp today, a BS2SX mounted on an education board.

I've spend the last hour trying to find out how it handles strings. But in my manual the word string is not to be found.

How do·I declare a variable og type string ?
How do I·assing a·value to the variable ?
How do I compare 2 strings ?

Thanks in advance
Anders

dk_akj · 2004-08-05 19:59

//akj

Jon Williams · 2004-08-05 21:10

There is no string type in PBASIC, therefore you cannot compare strings (easily). String data can be stored in an array of bytes, and the STR modifier can be used to "print" these strings using DEBUG or SEROUT. To compare you would have to do it byte-by-byte.

When strings are needed for displays, etc., they're typically stored in DATA statements. Like this:

Msg1    DATA    "This is a text string", 0

By making them zero-terminated, a simple subroutine can be used to "print" them:

Print_String: 
  DO 
    READ eeAddr, char 
    eeAddr = eeAddr + 1 
    IF (char = 0) THEN EXIT 
    DEBUG char 
  LOOP 
  RETURN

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Jon Williams
Applications Engineer, Parallax
Dallas Office

Using strings

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