Re: Array causing trouble ?

Willy · Guest

I have this problem with some code I wrote. It sends AT commands to a modem, the code works, it sends the commands and the getc() in the serial function works because I can put it into a temp variable and send it again. I have created an array called Buffer and use getc to place the characters into this array. For some reason it will not do this, the array stays empty ! Could someone please tell me what I am doing wrong !

#include <16c84.H>

#fuses HS,NOWDT,NOPROTECT

#use delay(clock=4000000)
#use rs232(baud=9600, xmit=PIN_B1, rcv=PIN_B0)

byte buffer[14]; //Buffer for number
byte in_byte = 0; //To increment Buffer

void input_byte(void)
{
buffer[in_byte]=getc(); //Read character into Buffer
in_bit++; //Increment array position
}

main()
{
int count = 0; //For reading in characters from modem

output_float(PIN_B0);
output_high(PIN_B1);

while(TRUE)
{

in_byte = 0; //Reset increment for Buffer

printf("AT+CMGD=1\r"); //Delete SMS in position 1
delay_ms(2000); //Delay for delete

printf("AT+CMGF=1\r"); //Setup SMS text mode
delay_ms(1000);
while(input(PIN_B0)); //Wait for SMS rec indication
delay_ms(1000);

output_high(PIN_B2); //Turn LED on to indicate SMS rec

printf("AT+CMGR=1\r"); //Read SMS from modem

while(input(PIN_B0)); //Wait for 1st bit

while(count < 36) //Read in bytes
{
if(count >= 22) //Read in required bytes depending on buffer size
input_byte(); //Call input function
else
getc(); //Discard not wanted bytes
count++;
}

count = 0; //Reset read in byte counter

delay_ms(3000); //Delay before send

printf("AT+CMGS="); //Send SMS
printf(buffer); //Send Buffer
delay_ms(1000);
printf("\r"); //End command
delay_ms(1000);
printf("New number is: "); //Message to send
printf(buffer); //Message to send
delay_ms(1000);
putc(0x1a); //Send control Z

delay_ms(5000); //Wait for messsage to be sent
} //Return to beginning to start process agian
}
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This message was ported from CCS's old forum
Original Post ID: 965

Ian McCrum · Guest

The write to buffer routine compiles and works for me.
YOu have mistyped the array increment instruction,

in_bit++;

should be

in_byte++;


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This message was ported from CCS's old forum
Original Post ID: 968

Willy · Guest

:=The write to buffer routine compiles and works for me.
:=YOu have mistyped the array increment instruction,
:=
:=in_bit++;
:=
:=should be
:=
:=in_byte++;
:=
:=

Hi Ian

That was a mistake which I was aware of, thankyou for pointing that out to me. The problem I am having is that the first array element gets filled with the value of 14 and is incremented throughout the array. I have tried loading the array with 0's first but it still happens. I simulate the modem using hyper terminal and print the array and that is what I got.

Regards
Willy
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This message was ported from CCS's old forum
Original Post ID: 971

Willy · Guest

:=:=The write to buffer routine compiles and works for me.
:=:=YOu have mistyped the array increment instruction,
:=:=
:=:=in_bit++;
:=:=
:=:=should be
:=:=
:=:=in_byte++;
:=:=
:=:=
:=
:=Hi Ian
:=
:=That was a mistake which I was aware of, thankyou for pointing that out to me. The problem I am having is that the first array element gets filled with the value of 14 and is incremented throughout the array. I have tried loading the array with 0's first but it is still replaced by 14 up . I simulate the modem using hyper terminal and print the array and that is what I got.
:=
:=Regards
:=Willy

Hi

I am using Mplab and I noticed that the array is filled with the values 14 up even before I run the program. If I declare another variable before the array its starts at 15 up etc, what could be causing this ?? Can anyone help.

Regards and Thanks
Willy
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This message was ported from CCS's old forum
Original Post ID: 973

Ian McCrum · Guest

Willy, I only had time for a quick look at the machine code. The code to fill the buffer looks ok, but that area of memory may be getting corrupted by the printf(buffer) statement, which is a strange way to use printf by the way? do you input leading and trailing double quotes?

Does printf("\%s",buffer) work, IF THE LAST LOCATION IN BUFFER HOLDS A ZERO!!!!

I'm a bit new to the CCS compiler by the way...
Cheers Ian
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This message was ported from CCS's old forum
Original Post ID: 977

Willy · Guest

Hi Ian
\%s does not work but \%c,\%0x,\%d work. I just don't understand way the array "buffer" is filled with the same values as the line numbers, because if I create more variables it moves the buffer array and it takes on the values of the new line numbers. This code was working at a stage but then I added some more and this started happening. Strange !!

Cheers
Willy
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This message was ported from CCS's old forum
Original Post ID: 978

Neutone · Joined: 08 Sep 2003 Posts: 839 Location: Houston

Your buffer is not really a string is it? To send and array of bytes;

for(TempInt1= 0; TempInt1<= 14; TempInt1++)
{
putc(Buffer[TempInt1]);
}
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This message was ported from CCS's old forum
Original Post ID: 979

Willy · Guest

:=Your buffer is not really a string is it? To send and array of bytes;
:=
:=for(TempInt1= 0; TempInt1<= 14; TempInt1++)
:= {
:= putc(Buffer[TempInt1]);
:= }

The problem I am having is that the first array element gets filled with the value of 14 (same as line number)and is incremented throughout the array. I have tried loading the array with 0's first but it is still replaced by 14 up . I simulate the modem using hyper terminal and print the array and that is what I got.
I noticed the array "buffer" is filled with the same values as the line numbers, because if I create more variables it moves the buffer array and it takes on the values of the new line numbers. This code was working at a stage but then I added some more and this started happening. Using printf(in_buffer); worked, but no I have a problem placing the recieved data into the array because it gets filled by other data. Could it not be compiler problem ?

Regards
Willy
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This message was ported from CCS's old forum
Original Post ID: 980

Willy · Guest

:=Your buffer is not really a string is it? To send and array of bytes;
:=
:=for(TempInt1= 0; TempInt1<= 14; TempInt1++)
:= {
:= putc(Buffer[TempInt1]);
:= }
The problem I am having is that the first array element gets filled with the value of 14 (same as line number)and is incremented throughout the array. I have tried loading the array with 0's first but it is still replaced by 14 up . I simulate the modem using hyper terminal and print the array and that is what I got.
I noticed the array "buffer" is filled with the same values as the line numbers, because if I create more variables it moves the buffer array and it takes on the values of the new line numbers. This code was working at a stage but then I added some more and this started happening. Using printf(in_buffer); worked, but now I have a problem placing the recieved data into the array because it gets filled by other data. Could it not be compiler problem ?

Regards
Willy
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This message was ported from CCS's old forum
Original Post ID: 981

Ian McCrum · Guest

:=Hi Ian
:=\%s does not work

. This code was working at a stage but then I added some more and this started happening. Strange !!

Oops, yes I checked the manual, \%s not available in version 2
(you do get it in version 3!).

I still think your printf'f look funny. I supppose you need to cut out lines until it resumes working... try removing all the printfs, or at least the printf(buffer) statements

As I said, fairly new to ccs C

Good luck
Ian
p.s if you get time have a go with my problem, earlier in the BBS... a bug in delay_us() I think
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This message was ported from CCS's old forum
Original Post ID: 989

Tone · Guest

Hello,

I thought that the printf(buffer) statement looked funny also. When ever you call a function that expects a string as a parameter, it MUST be NULL terminated. IE have a byte set to zero somewhere in the array. Not doing so will cause indeterminate results and is a probable cause of corruption elsewhere in memory.

My 2p worth.

Tone.
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This message was ported from CCS's old forum
Original Post ID: 1010

Tone · Guest

I forgot to add (also for the benefit of Ian) that there is a probably a better way of sending strings to the serial port:

putc(buffer);

assuming you know the string to be NULL terminated of course :)

This is a Peculiarity of CCS C, in that if you pass a string to a function that expects a type char or int as a parameter, then the function gets repeatedly called with every element of the array until the NULL is reached.

Regards,

Tone.
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This message was ported from CCS's old forum
Original Post ID: 1011