PIC16F877A串口發(fā)送字符串問題

PIC16F877A串口發(fā)送，查詢方式，就為了調(diào)出這個(gè)費(fèi)了我一天時(shí)間，原來是串口芯片電壓問題，現(xiàn)總結(jié)如下：

1、注意232串口芯片供電電壓，有5V和3.3V的

2、注意TXD、RXD接線，單片機(jī)的TXD接232芯片的R2OUT，單片機(jī)的RXD接232芯片的T2IN

3、注意ESP8266的UTXD接MCU的RX，URXD接MCU的TX

4、注意ESP8266的UTXD接232的T2IN，URXD接232的R2OUT

5、串口波特率設(shè)置成9600

6、注意連接線的可靠性，如果用線連的話一定要檢查線和插座是否穩(wěn)定連接

7、系統(tǒng)連線如下圖所示

PIC16F877A串口發(fā)送 - allegro_tyc - allegro_tyc的博客

//以下是串口發(fā)送程序

#include

#define uchar unsigned char

#define uint unsigned int

__CONFIG(0x3B32);

void delay2ms(uint x)

{

uint a,b;

for(a=x; a>0; a--)

for(b=152; b>0; b--);

}

void UART_SendByte(unsigned char dat)

{

TXREG=dat;

while(TRMT==0);

}

void serial_init()

{

TRISC=0xbf;//設(shè)置RX為輸入，TX為輸出

TXSTA=0x24;

RCSTA=0x80;

SPBRG=0x33;//本人使用的是8MHz晶振，9600=8000000/(16*(X+1))->X=51->X=0x33

GIE=1;

PEIE=1;

RCIE=1;

}

void main()

{

serial_init();

while(1)

{

UART_SendByte(0x31);

UART_SendByte(0x32);

UART_SendByte(0x33);

delay2ms(500);

}

}

//以下是MCU發(fā)送AT命名給ESP8266的程序

#include

#define uchar unsigned char

#define uint unsigned int

#define LEDRD1

__CONFIG(0x3B32);

#define LED_OPEN() (LED=1)

#define LED_CLOSE() (LED=0)

#defineCPU_FOSC8000000

#defineBAUD9600

unsigned char* LYMS=AT+CWMODE=3r;

unsigned char* SZLY=AT+CWSAP=ESP8277_CYT,1234567890,11,3r;

unsigned char* RST=AT+RSTr;

unsigned char* LCAP=AT+CWLAPr;

unsigned char* SZDLJ=AT+CIPMUX=1r;

unsigned char* KQFU=AT+CIPSERVER=1,5000r;

unsigned char* FSSJ=AT+CIFSRr;

void delay2ms(uint x)

{

uint a,b;

for(a=x; a>0; a--)

for(b=152; b>0; b--);

}

void sys_init()

{

TRISD=0x00;//設(shè)置PORTD口為輸出

}

void usart_init()

{

TRISC=0xbf;//設(shè)置RX為輸入，TX為輸出

TXSTA=0x24;

RCSTA=0x80;

SPBRG=0x33;//本人使用的是8MHz晶振，9600=8000000/(16*(X+1))->X=51->X=0x33

GIE=1;

PEIE=1;

RCIE=1;

}

void usart0_putchar(unsigned char data)

{

while (!TRMT);

TXREG = data;

}

void print(unsigned char* p_string)

{

while (*p_string)

{

if (*p_string != 'r')

{

usart0_putchar(*p_string);

}

else

{

usart0_putchar('r');

usart0_putchar('n');

}

p_string++;

}

}

void send_command()

{

print(LYMS);delay2ms(500);delay2ms(500);

print(SZLY);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(RST);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(LCAP);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(SZDLJ);delay2ms(500);delay2ms(500);

print(KQFU);delay2ms(500);delay2ms(500);

print(FSSJ);delay2ms(500);delay2ms(500);

}

void main()

{

sys_init();

usart_init();

send_command();

while(1)

{

PORTD = 0xff;

delay2ms(500);

PORTD = 0x00;

delay2ms(500);

}

}

//以下是MCU發(fā)送AT命名給ESP8266的程序，并接收命令、解析并作出反應(yīng)

#include

#define uchar unsigned char

#define uint unsigned int

unsigned char RX_Buffer[32];

unsigned char RX_CNT=0;

#define LED1RD1

#define LED2RD2

#define LED3RD3

__CONFIG(0x3B32);

#define LED1_OPEN() (LED1=1)

#define LED1_CLOSE() (LED1=0)

#define LED2_OPEN() (LED2=1)

#define LED2_CLOSE() (LED2=0)

#define LED3_OPEN() (LED3=1)

#define LED3_CLOSE() (LED3=0)

#defineCPU_FOSC8000000

#defineBAUD9600

unsigned char* LYMS=AT+CWMODE=3r;

unsigned char* SZLY=AT+CWSAP=ESP8277_TYC,1234567890,11,3r;

unsigned char* RST=AT+RSTr;

unsigned char* LCAP=AT+CWLAPr;

unsigned char* SZDLJ=AT+CIPMUX=1r;

unsigned char* KQFU=AT+CIPSERVER=1,5000r;

unsigned char* FSSJ=AT+CIFSRr;

void delay2ms(uint x)

{

uint a,b;

for(a=x; a>0; a--)

for(b=152; b>0; b--);

}

void sys_init()

{

TRISD=0x00;//設(shè)置PORTD口為輸出

}

void usart_init()

{

TRISC=0x80;//設(shè)置RX為輸入，TX為輸出

TXSTA=0x24;

RCSTA=0x90;

SPBRG=0x33;//本人使用的是8MHz晶振，9600=8000000/(16*(X+1))->X=51->X=0x33

RCIE=0x01;

TXEN=0x01;

TXIE=0x01;

PEIE=0x01; //外部中斷使能

GIE=1;//總中斷使能

}

void usart0_putchar(unsigned char data)

{

while (!TRMT);

TXREG = data;

}

void print(unsigned char* p_string)

{

while (*p_string)

{

if (*p_string != 'r')

{

usart0_putchar(*p_string);

}

else

{

usart0_putchar('r');

usart0_putchar('n');

}

p_string++;

}

}

void send_command()

{

print(LYMS);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(SZLY);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(RST);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(LCAP);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(SZDLJ);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(KQFU);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

print(FSSJ);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);delay2ms(500);

}

void interrupt usart(void)

{

if(RCIERCIF)

{

//TXREG = RCREG;

RX_Buffer[RX_CNT] = RCREG;

if(RX_Buffer[0]==0x45)

RX_CNT++;

else

RX_CNT=0;

if(RX_CNT>=10)

{

if(RX_Buffer[0]==0x45RX_Buffer[1]==0x53RX_Buffer[2]==0x50)

{

if(RX_Buffer[4]==0x4CRX_Buffer[5]==0x45RX_Buffer[6]==0x44)

{

if(RX_Buffer[7]==0x31)

{

if(RX_Buffer[3]==0x4B)

LED1_OPEN();

if(RX_Buffer[3]==0x47)

LED1_CLOSE();

}

}

}

RX_CNT=0;

}

}

}

void main()

{

sys_init();

usart_init();

send_command();

LED1_OPEN();

LED2_OPEN();

LED3_OPEN();

while(1);

}