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Hi all,
I'm using 89C52 controller in my application. I'm using a 90 byte buffer to store received message from UART. Based on this received message I'm controlling I/O ports. The same buffer I'm using for transmitting the application dependent internal status message.
To identify the message I'm using absolute address position for example, if(arr[59] == '*'){do something;}
every first message after reset this is working fine. After that the control hangs somewhere thus its giving undetermined behavior.
I set the memory model as Large: all variables in XDATA.
I hope some address overflow is happening here.
Can anyone help me to resolve this issue.
Thanks in Advance.
Regards, Ramesh
Here is my code fragment:
#include<serial.h> #include <AT89X52.H> unsigned char message[35]; unsigned char Request[35]; main() { unsigned char i,j,;
Init_Uart(); // UART functionlity working fine with 9600 baud while(1) { for(i=0;i<=35;i++) { message[i]=RX_CHAR(); //Rx buffer for first 35 char's controll waits here for incoming char process=1; }
if(process==1) {
if(message[25]=='*') // I'm sure that this characters are 26th character always from transmitter {pass =1; TestLED=ON;} else if(message[25]=='#') {pass =0;TestLED=OFF;} process =0; }
if(pass==1) { for(j=0;j<=35;j++) { Request[j]= 'A';
} Send_Str(Request); // Request array is transmitted Note this subroutine is tested working correctly
} else if( pass==0) { for(j=0;j<=35;j++) { Request[j]= 'B';
} Send_Str(Request); // Request array is transmitted }
} }
Please suggest.
re-post using the proper tags please!
Here is the code again..
#include<serial.h> #include <AT89X52.H>
unsigned char message[35]; unsigned char Request[35];
main() { unsigned char i,j;
// UART functionlity working fine with 9600 baud
Init_Uart(); while(1) { for(i=0;i<=35;i++)
{
//Rx buffer for first 35 char's // controll waits here for incoming char
message[i]=RX_CHAR(); process=1;
}
if(process==1)
// I'm sure that this characters are 26th // character always from transmitter
if(message[25]=='*')
pass =1; TestLED=ON;
else if(message[25]=='#')
pass =0; TestLED=OFF;
process =0;
if(pass==1)
for(j=0;j<=35;j++)
Request[j]= 'A';
// Request array is transmitted Note this // subroutine is tested working correctly.
Send_Str(Request); }
else if( pass==0)
Request[j]= 'B';
Send_Str(Request);
} } }
Thanks
unsigned char message[35]; unsigned char Request[35]; for(i=0;i<=35;i++) { //Rx buffer for first 35 char's // controll waits here for incoming char message[i]=RX_CHAR(); process=1; } for(j=0;j<=35;j++) { Request[j]= 'A'; }
YOU ARE FILLIN G A 35 CHARACTER ARRAY WIT H36 CHARACTERS!
THAT IS OVERFLOW!
narak, don't you think it is only appropriate to also SCREAM in the code that you post?!
<QUOTE>don't you think it is only appropriate to also SCREAM in the code that you post?!</QUOTE>
HE DOES NOT WANT TO LISTEN TO MY ANSWER WHO I THINK IS CORRE CT!
IS HE DEF?
the OP probably already implemented your careful advise. there is no need to use UPPERCASE. that won't make his listen - just annoy everyone else.
Hi Narak,
I had already modified the code as below. But still its not working.
for(i=0;i<=34;i++) { message[i]=RX_CHAR();
I'm using Uvision3 IDE version 3.30a. I have not tried out with older version of IDE. Will it cause any problem??