PIC18F45K222 EUSART serial communication help...

[VoltVolt]

PIC18F45K22 EUSART serial communication(transmit only) help...

hi everyone, just want to ask is there any problem from the below codes?
I just want to print out "helloword" by using serial communication
I'm using PIC18F45K22 and MPLABX IDE compiler...
The codes can be smoothly run but it cannot be print out...
Btw, i don't have interrupt, it is just a test code....

#include <htc.h>
#include <string.h>
char sendBuffer[11];
char sendPosition=0;
void sendUartString(const char string[10]);
void init()
{
// Asynchronous Transmission Setup
// 1. Initialize the SPBRGHx:SPBRGx register pair and the BRGH and BRG16 bits to achieve the desired baud rate
        SPBRGH2=0X01;
        SPBRG2=0XA0;
	TXSTA2bits.BRGH=1;
	BAUDCON2bits.BRG16=1;
// 2. Set the RXx/DTx and TXx/CKx TRIS controls to ?1?.
	TRISB = 0b11000000;	//set TX2 and RX2 as output

// 3. Enable the asynchronous serial port by clearing the SYNC bit and setting the SPEN bit.
	ANSELB = 0;	//disable ANSEL
	SYNC2 = 0;	//asynchronous mode
	SPEN2 = 1;	//enable EUSART

// 4. If 9-bit transmission is desired, set the TX9 control bit. A set ninth data bit will indicate that the eight Least Significant data bits are an address when the receiver is set for address detection.
// 5. Set the CKTXP control bit if inverted transmit data polarity is desired.
// 6. Enable the transmission by setting the TXEN control bit. This will cause the TXxIF interrupt bit to be set.
	TXEN2 = 1;
// 7. If interrupts are desired, set the TXxIE interrupt enable bit. An interrupt will occur immediately provided that the GIE/GIEH and PEIE/GIEL bits of the INTCON register are also set.

// 8. If 9-bit transmission is selected, the ninth bit should be loaded into the TX9D data bit.
// 9. Load 8-bit data into the TXREGx register. This will start the transmission.
}
void main()
{
	init();
	//now you want to send something, so first load a string into the sendBuffer
        while(1)
        {
		//sendUartString("helloworld");
        }
}


void sendUartString(const char string[10])
{
	strcpy(sendBuffer,string); //please check the correct command,copy string[] to sendBuffer[]

	sendPosition=0; //start sending first char
	while((sendPosition!= strlen(sendBuffer)) && sendPosition<10 )
	{
		if(TX2IF==1)//if Transmit register is empty
		{
			TX2REG=sendBuffer[sendPosition]; //send one more char
			sendPosition++;
		}
	}
}

 

[jayanth.devarayanadurga]

Re: PIC18F45K22 EUSART serial communication(transmit only) help...

See if Tx pin has to be set as output pin.

 

[VoltVolt]

Re: PIC18F45K22 EUSART serial communication(transmit only) help...

but from the datasheet it says that
"2. Set the RXx/DTx and TXx/CKx TRIS controls to 1"
So what I did:
TRISB = 0b11000000; //set TX2 and RX2 as input

 

[jayanth.devarayanadurga]

Re: PIC18F45K22 EUSART serial communication(transmit only) help...

What is the Fosc used? 16 MHz?

Try this

---

Code C - [expand]
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while((sendPosition!= strlen(sendBuffer)) && sendPosition<10 )
{
    TX2REG=sendBuffer[sendPosition++]; //send one more char
    while(TX2IF);
}

---

 

[VoltVolt]

Re: PIC18F45K22 EUSART serial communication(transmit only) help...

if not mistaken... is internal oscillator?
my internal oscillator should be 16MHz...
Owh!
so I should set my OSCCON? haha

- - - Updated - - -

I edited you code and add OSCCON register...
add the configuration bits...
it still not working...
But it successfully build...

Below shows the code I edited...

#include <htc.h>
#include <string.h>

/* Start of configuration fuses*/
#pragma config IESO=OFF, FOSC=INTIO67,PRICLKEN=OFF,FCMEN =OFF,PLLCFG=ON,BOREN=ON,BORV=250
#pragma config WDTEN=OFF
#pragma config P2BMX=PORTC0,CCP2MX=PORTC1,PBADEN=OFF,CCP3MX=PORTE0,MCLRE=INTMCLR,HFOFST=OFF,T3CMX=PORTC0
#pragma config DEBUG=OFF,STVREN=ON,XINST=OFF,LVP=OFF
#pragma config CP0=OFF,CP1=OFF,CP2=OFF,CP3=OFF
#pragma config CPB=OFF,CPD=OFF
#pragma config WRT0=ON,WRT1=ON,WRT2=ON,WRT3=ON
#pragma config WRTB=ON,WRTC=ON,WRTD=ON
/* end of configuration fuses */

char sendBuffer[11];
char sendPosition = 0;
void sendUartString(const char string[10]);

void init() {
    OSCCON = 0b11110011; //16MHz internal oscillator
    OSCCON2 = 0b00000000;

    // Asynchronous Transmission Setup
    // 1. Initialize the SPBRGHx:SPBRGx register pair and the BRGH and BRG16 bits to achieve the desired baud rate
    SPBRGH2 = 0X01;
    SPBRG2 = 0XA0;
    TXSTA2bits.BRGH = 1;
    BAUDCON2bits.BRG16 = 1;
    // 2. Set the RXx/DTx and TXx/CKx TRIS controls to ?1?.
    TRISB = 0b11000000; //set TX2 and RX2 as input

    // 3. Enable the asynchronous serial port by clearing the SYNC bit and setting the SPEN bit.
    ANSELB = 0; //disable ANSEL
    SYNC2 = 0; //asynchronous mode
    SPEN2 = 1; //enable EUSART

    // 4. If 9-bit transmission is desired, set the TX9 control bit. A set ninth data bit will indicate that the eight Least Significant data bits are an address when the receiver is set for address detection.
    // 5. Set the CKTXP control bit if inverted transmit data polarity is desired.
    // 6. Enable the transmission by setting the TXEN control bit. This will cause the TXxIF interrupt bit to be set.
    TXEN2 = 1;
    // 7. If interrupts are desired, set the TXxIE interrupt enable bit. An interrupt will occur immediately provided that the GIE/GIEH and PEIE/GIEL bits of the INTCON register are also set.
    //TX2IE = 1;
    //GIE = 1;
    //PEIE = 1;
    // 8. If 9-bit transmission is selected, the ninth bit should be loaded into the TX9D data bit.
    // 9. Load 8-bit data into the TXREGx register. This will start the transmission.
}

void main() {
    init();
    //now you want to send something, so first load a string into the sendBuffer
    while (1) TXREG2 = 'H';
    //while(1)
    //sendUartString("helloworld");
}

void sendUartString(const char string[10]) {
    strcpy(sendBuffer, string); //please check the correct command,copy string[] to sendBuffer[]

    sendPosition = 0; //start sending first char
    //    while ((sendPosition != strlen(sendBuffer)) && sendPosition < 10) {
    //        if (TX2IF == 1)//if Transmit register is empty
    //        {
    //            TX2REG = sendBuffer[sendPosition]; //send one more char
    //            sendPosition++;
    //        }
    //    }
    while ((sendPosition != strlen(sendBuffer)) && sendPosition < 10) {
        TX2REG = sendBuffer[sendPosition++]; //send one more char
        while (TX2IF);
    }
}

 

[paulfjujo]

hello,

in your post #1 , how do you want to send somewhat with a comment in front of your function.
and add some delay between invoice..

void main()
{
    init();
    //now you want to send something, so first load a string into the sendBuffer
        while(1)
        {
        [B][COLOR=#FF0000]//[/COLOR][/B]sendUartString("helloworld");
        }
}

and in post#5

void main()
 {
 init();
while(1)
{
    if (TX2IF == 1) //if Transmit register is empty
           {
              TX2REG = 'H'
           }
    // add here some delay !
 }
}

 

[jayanth.devarayanadurga]

Re: PIC18F45K22 EUSART serial communication(transmit only) help...

See if you have to add

---

Code C - [expand]
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#define _XTAL_FREQ 16000000

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