Wednesday, 25 July 2012

Example coding to know the response from GSM Modem.

#include <pic.h>
#use delay (clock=20000000)
#fuses hs,nolvp,nowdt,noprotect,nobrownout
#use rs232(baud=9600, bits=8, xmit=pin_C6, rcv=pin_C7, parity=n, stream=GSM)
#byte porta=5
#byte portb=6
#byte portc=7
#include "flex_lcd.c"

volatile int  counter_search=0;            //counter to traverse the array
volatile int  counter_read=0;             //counter to fill the array
volatile Char Recieve_String[70];   //buffer for incoming data
int GET_OK(int Stop_Search);             // Just searches for an OK.
int TEST_AT();

void main()
{
       
         set_tris_a( 0x00 );     // to avoid floating pins
         set_tris_b( 0x00 );
         output_b(0X00);
         set_tris_c( 0x80 );
       
         enable_interrupts(INT_RDA);  // enable RDA interrupts
         enable_interrupts(GLOBAL);   // enable global ints
       
         delay_ms(500);
         lcd_init();
         lcd_gotoxy(3,1);
         lcd_putc("GET RESPONSE");
         delay_ms(1000);
       
         delay_ms(1000);
         TEST_AT();

}

int TEST_AT()
{
         counter_read=0;

         lcd_gotoxy(8,2);
         lcd_putc("AT");
         printf("AT\n\r");                //send command

         While(counter_read<=8)             //"A T \R \R \N O K \R \N" characters returned by modem
         {
         }

         counter_read=0;
         Delay_ms(500);

         if(GET_OK(0X0A))
         {  lcd_gotoxy(8,2);
            lcd_putc("OK");
            return(1); }
         else return(0);

}

int GET_OK(Stop_Search)
{
         counter_search=0;

         while((Recieve_String[counter_search]!='O')&&(counter_search<Stop_Search))
         {
            counter_search++;     //obvious
         }

         if((Recieve_String[counter_search]=='O')&&(Recieve_String[counter_search+1]=='K'))
         {
            counter_search=0;
            return(1);
         }
         return(0);
         counter_search=0;
}

#int_RDA
void RDA_isr()
{
   Recieve_String[counter_read]=getchar(GSM);
   counter_read++;
   if(counter_read==69)
      counter_read=0;
}

Tuesday, 24 July 2012

find info I to V converter dgn btol kn cct connection

Monday, 23 July 2012

btol kn cct in ares..tmbah voltage regulator

Friday, 20 July 2012

construct cct at ares..

Thursday, 19 July 2012

....

Wednesday, 18 July 2012

9am - 1 pm
     Continue with GSM modem.


Sending SMS

     Flow of AT command that must be use to communicate with the GSM modem (between GSM and PIC).

AT+CMGF= 1 ---> set PDU Mode = 1, Text Mode = 0

Enter : \n\r

Example coding : printf ("AT+...")

                               putc (26)

                               putc (0x14) <---- value of 14 is from ASCII Table

Sent SMS using AT Command from Hyper Terminal

2pm - 5pm

     Mr. Mazran give me another task to construct basic circuit of instrumentation amplifier 1NA114 in breadboard by follow the value that he need.

Component: Variable resistor: 10k Ohm, 50k Ohm, resistor: 2.2k Ohm (4 unit), Supply: adapter            

                      12V, 1NA114 amplifier

Circuit that have been constructed:

Tuesday, 17 July 2012

     Continue with GSM task. Try solve problem how to get GSM receive our coding and the function "CALL READY" also not interframe. Other thing that Mr. Mazran told us which try use interrupt function.

UART

UART is stand for Universal Asynchronous Receiver Transmitter. UART signal is use to send and receive data over the three wires, which is TX, RX and GND. Synchronous transmission requires the sender and receiver to share the same clock signal. While the Synchronous transmission allow the data is sent without a clock signal sent but the sending and receiver must to operate at the same timing parameter known as Baud Rate.