Pic : RS232 communication

RS232 communication on PIC

I will make the remote controller device by using XBEE. Before that, PC and PIC communication is tested.

18f2320 is used.

RX/TX port are used and TRISCbits.RC7 is set to be input I/O and TRISCbits.RC6 is set to output one. Also TRISCbits.RC6 is set to high.

Please check below setting is set correctly.

• SPEN (RCSTA<7>) bit must be set (= 1)

• TRISC<7> bit must be set (= 1)

• TRISC<6> bit must be cleared (= 0)

Below program needs windows' hyper terminal input.

10MHz clock is multiplied by config. HSPLL so clock is 40MHz.

Then, baud rate is 115.2kHz. 

//////////////////////////////////

//main program

//////////////////////////////////

#include <p18f2320.h>

#include <i2c.h>

#include <usart.h>

#include "i2cLCD.h"

#include "wait.h"

#pragma config OSC=HSPLL, FSCM=OFF, IESO=OFF, PWRT=ON

#pragma config BOR=ON, BORV=27, WDT=OFF, WDTPS=1024

#pragma config MCLRE=ON, PBAD=DIG, CCP2MX=C1

#pragma config STVR=OFF, LVP=OFF, DEBUG=OFF

#pragma config CP0=OFF, CP1=OFF, CP2=OFF, CP3=OFF, CPB=OFF

#pragma config CPD=OFF, WRT0=OFF, WRT1=OFF, WRT2=OFF, WRT3=OFF

#pragma config WRTB=OFF, WRTC=OFF, WRTD=OFF, EBTR0=OFF

#pragma config EBTR1=OFF, EBTR2=OFF, EBTR3=OFF, EBTRB=OFF

void main(void)

{

char test[]="AQM0802A";

char inputFromPC[] = "From PC";

char inputMsg[]="\r\nInput 5 characteristic= ";

char bufLcd[10]={0,0,0,0,0,0,0,0,0,0};

//I2C initialization

TRISC = 0x18;

SSPADD = 24; //MCLK40MHz / (4*(SSPAD+1)) = 400khz

  SSPCON1 = 0b00101000;

wait_ms(100);

lcdIni();

lcdCommand(LCD_1ST_LINE);

lcdPrintSting(test);

wait_ms(200);

lcdCommand(LCD_CLEAR);

//USART

TRISC |= 0x80;

LATC = 0x40; 

RCSTAbits.SPEN=1;

OpenUSART(USART_TX_INT_OFF & USART_RX_INT_OFF &

USART_ASYNCH_MODE & USART_EIGHT_BIT &

USART_CONT_RX & USART_BRGH_HIGH,21);

while(1)

{

putsUSART(inputMsg);

getsUSART(bufLcd,5);

lcdCommand(LCD_CLEAR);

wait_ms(2);

lcdCommand(LCD_1ST_LINE);

lcdPrintSting(inputFromPC);

lcdCommand(LCD_2ND_LINE);

lcdPrintSting(bufLcd);

}

}