RECEIVER PROBLEM IN UART

[Abinesh]

I am trting to transmit and receive character in pic.I can transmit character which i checked through hyperterminal but i cant receive character the thing is i cant properly set the receiver port. the interrrupt is not set while receiving.can any one help with me in this problem.

 

 

Thanks in advance.

 

[AJISH ALFRED]

Hi Abinesh,

If you have trouble coding for the interrupt, then try ‘busy flag checking’ method. Please post your code which you have written so far.

[Dhananjaya]

pleas help me…

 i am also facing same problem … I have tested the code in pc hyperterminal for both send &Receive SMS through GSM SIM 300 with PIC 16F877a Micro controller through MAX 232 but when i connect GSm SIM 300 with PIC 16F877a Micro controller its not supporting so without connecting MAX 232 its working only for (I can transmit character) SEND ing Message and daling the call but its not receiving any thing..without using MAX 232 what is the problem…

[Ashutosh Bhatt]

there are two interrupts for UART

1) with transmit data

2) with receive data

 

both have to be saparately enabled or disabled.

one of the best way to test UART with computer is use LOOP BACK mode.

send character from hyperterminal and receive same from controller on hyper terminal screen.

[Dhananjaya]

 

 

I have tested loop back mode for PIC  microcontroller with PC hyperterminal is OK

 

how to check the receiving code …in PIC  microcontroller with GSM SIM 300 with LCD

and then how to compare the receiving data..from predefined data

[Ashutosh Bhatt]

checking of receive code is very simple

you will get ASCII characters for each letter or digit. like 0x31 for digit 1 0x41 for letter A like wise.

mostly you will get string of such ASCII characters from any device like GSM modem or GPS receiver.

so what you have to do is store this command in string –  character type array

then just compare string using strcmp command in C language

[Dhananjaya]

 

 

 Dear Sir, 

 

    I have sending SMS through this i.e GSM SIM300 with PIC16F877A microcontroller I  have tested the code  for GSM SIM response like OK it will display on LCD i have written code like this

 

 

unsigned char i;

char buffer[25];

 

 

i=0;

while(!RCIF)

bufer[i++]=RCREG;

buffer=’’;

for(i=0;buffer!=’’;i++)

{

 

  lcd_goto(0x00+i);

  lcd_write(buffer);

}

 

in this case it will not entering for loop because codition is true for ‘’  for this i think it will not receiving any thing… and some times garbage value will display on LCD  what you have told GSM SIM data will give  a ASCII value so how to converting this ascii value into display in LCD is it possible and then how to comparing string for GSM Respose like OK….

 

otherwise please  give me a code for initialise the Receiving and Transmitting configuration bits for PIC16F877A Headder file..

[manimaran]

Answer is simple…u r checking the code as buffer!=’’

 

But you are giving the value as buffer!=’’.. Then it checks this the condition is not satisfied. So it exits the loop..

[erwin]

use your own terminating character in my case i’ve used *….

[Author]

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