The previous post is the way to solve your problem, but...

If you are programming a PIC you should not fear pointers.  Just realize
that once you have that 'get it' moment they won't be confusing any more.

One thing to keep in mind is that C has a few notation short cuts that make
things less consistant.

Char buffer[20];

This one statement does several things.

1) it sets aside 20 bytes (each char is 1 byte) of memory.
2) it declares a char* named 'buffer'
3) it sets the value of the char* buffer to the beginning of the memory it
set aside.

Number 2 is the confusing part. It does not look like you are declaring a
pointer, but in most respects buffer behaves as if it was declared "char*
buffer"

The next confusing thing; Variables of type char* are assumed to point to a
memory location that has 0 or more byte values that correspond to ASCII
characters (65 means 'A' and is OK, 200 means nothing in ASCII and is not
OK) and ending in the value 0 (NULL).  The 0 lets functions know how long
the string is.

The C compiler sets aside memory for string literals (like "dog") with one
extra byte that it sets to 0 (NULL).

Now strcat only works with char* (pointers to strings).  There are library
functions to convert standard types to there ASCII string representations.

--BobG

-----Original Message-----
From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU]On
Behalf Of John Pfaff
Sent: Friday, July 20, 2001 10:48 AM
To: PICLIST@MITVMA.MIT.EDU
Subject: Re: [PIC]: Tied up with String: OR the String Cheese Incident

Why not this:

{
    char ampm[3] = "PM";        // This can be set to "AM" or "PM",
depending
on time
    int Hours, Minutes;

    printf( "%d:%02d %s", Hours, Minutes, ampm );
}

or even this if you really want to build a string and perhaps use it
elsewhere as well

{
    char string1[20]
    char ampm[3] = "PM";
    int Hours, Minutes;

    sprintf( string1, "%d:%02d %s", Hours, Minutes, AmPm );
    printf( string1 );
}


Lawrence Lile wrote:
>
> I am perpetually confused by pointers in C, thus, I avoid them whenever
> possible.  (I have the same method of coping with the city bus system -
> don't use it)
>
> CCS has a number of string functions, which "return pointers" whatever
that
> means.  What I'd like to accomplish is this:
>
> I want to concatenate several items into a string, then pass that string
to
> PRINTF and squirt it out the RS232 port.
>
> One of the strings might be something like  "10:01 AM System ON" or " 7 28
> PM System OFF" (note the blinked colon)
>
> Here's a stab at it, prolly fulla bugs:
>
> Char string1[20];
> .
> .
> .
>
> STRCAT(string1, Hours);  // of course, Hours is an INT, not a string, how
to
> convert to a string?
> STRCAT(string1, ':');         // blinky colon
> STRCAT(string1, Minutes); // minutes, also still an INT not a string ???
> STRCAT(string1, 'PM');  // does this work with a buncha letters?
> etc.
> Printf(*string1);  // ??????????
>
> Any suggestions are welcome
>
> -- Lawrence Lile
> Sr. Project Engineer
> Salton inc. Toastmaster Div.
> 573-446-5661 Voice
> 573-446-5676 Fax

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