2017-09-04 311 views
6

我是8位PIC的固件编写新手,可以使用我的代码。我正在使用PIC16F1829来获取RX命令的LED模块。我只是试图在RX引脚接收到特定值时开启LED等基本设置,但甚至无法获得该设置。PIC16F1829 UART RX中断不能使用MPLABX和XC8编译器

想通过中断让UART工作,但在主循环中甚至无法使用轮询工作。我的中断向量在下面的代码中被注释掉了。

RX引脚:RC5

TX引脚:RB7

引脚来开启和关闭切换LED:RA5

引脚RA5工作正常打开和关闭切换LED。 TX引脚工作,虽然我还没有确认如果中断TXIF也不像RCIF不工作一样工作。

我试过阅读RCIF和PIR1bits.RCIF。他们都编译了。两人都没有工作。我已经在两个不同的LED模块上对两个不同的PIC进行了尝试。他们打开了,但读取RX引脚也没有工作。

变量RXIN最初定义为3,因此由于主循环内的RXIN--循环,灯在启动时会闪烁3次,所以我知道它正在进入主循环。但据我所知,RCIF中断在RX引脚接收时不会触发。

我已经在示波器上确认信号进入RX并且使用相同的波特率从TX引脚输出,所以我认为波特率配置正确(300波特,8N1)。我还确认在示波器RX引脚接收强和干净5V信号。到目前为止,轮询RCIF或使用中断服务路由都没有工作。如果任何人都可以看到我的代码,我没有看到的问题,您的帮助将不胜感激。

我的代码:

#include <stdio.h> 
#include <stdlib.h> 
#include <xc.h> 

// This is for 300 baud rate 
#define _BAUD_PRESCALER_LOW_ 0x2A 
#define _BAUD_PRESCALER_HIGH_ 0x68 
#define _XTAL_FREQ 32000000 

#pragma config FOSC = INTOSC // Oscillator Selection->INTOSC oscillator: I/O function on CLKIN pin 
#pragma config WDTE = OFF // Watchdog Timer Enable->WDT enabled 
#pragma config PWRTE = OFF // Power-up Timer Enable->PWRT disabled 
#pragma config MCLRE = OFF // MCLR Pin Function Select->MCLR/VPP pin function is digital input 
#pragma config CP = OFF // Flash Program Memory Code Protection->Program memory code protection is disabled 
#pragma config CPD = OFF // Data Memory Code Protection->Data memory code protection is disabled 
#pragma config BOREN = ON // Brown-out Reset Enable->Brown-out Reset enabled 
#pragma config CLKOUTEN = OFF // Clock Out Enable->CLKOUT function is disabled. I/O or oscillator function on the CLKOUT pin 
#pragma config IESO = OFF // Internal/External Switchover->Internal/External Switchover mode is disabled 
#pragma config FCMEN = OFF // Fail-Safe Clock Monitor Enable->Fail-Safe Clock Monitor is disabled 

// CONFIG2 
#pragma config WRT = OFF // Flash Memory Self-Write Protection->Write protection off 
#pragma config PLLEN = ON // PLL Enable->4x PLL enabled 
#pragma config STVREN = ON // Stack Overflow/Underflow Reset Enable->Stack Overflow or Underflow will cause a Reset 
#pragma config BORV = LO // Brown-out Reset Voltage Selection->Brown-out Reset Voltage (Vbor), low trip point selected. 
#pragma config LVP = OFF 

int flagRXFramingError = 0; 
int flagRXOverrunError = 0; 
volatile unsigned char RXIN = 3; 

unsigned char UARTRead(){ 
    return RCREG; 
} 

void writeRXIN(unsigned char a){ 
    RXIN = a; 
} 

void TX(unsigned char a){ 
    while(!TXIF){} 
    TXREG = a; 
} 

int main(int argc, char** argv) { 

    // SCS FOSC; SPLLEN disabled; IRCF 8MHz_HF; 
    OSCCON = 0xF0; 
    // TUN 0; 
    OSCTUNE = 0x00; 
    // Set the secondary oscillator 
    // Wait for PLL to stabilize 
    while(PLLR == 0) 
    { 
    } 

    // WDTPS 1:65536; SWDTEN OFF; 
    WDTCON = 0x16; 
    __delay_ms(5); 

    GIE = 1; // Global interrupts enabled 
    __delay_ms(5); 
    PEIE = 1; // Active peripheral interrupts enabled 
    __delay_ms(5); 
    RCIE = 1; // Enable USART Receive interrupt 
    __delay_ms(5); 
    TXIE = 1; // Enable USART Transmitter interrupt 
    __delay_ms(5); 
    ADIE = 1; // Enable ADC interrupts 
    __delay_ms(5); 
    RXDTSEL = 0; // RX is on RC5 pin 
    __delay_ms(5); 
    TXCKSEL = 0; // TX is on RB7 pin 
    __delay_ms(5); 

    TRISC5 = 1; // RX pin set as input 
    __delay_ms(5); 

    SPEN = 1; // Serial Port Enabled 
    __delay_ms(5); 
    SYNC = 0; // Asynchronous mode 
    __delay_ms(5); 
    RX9 = 0; // 8 bit reception 
    __delay_ms(5); 
    TX9 = 0; // 8-bit transmission 
    __delay_ms(5); 
    CREN = 1; // Receiver enabled 
    __delay_ms(5); 
    TXEN = 1; // Transmitter enabled 
    __delay_ms(5); 
    BRG16 = 1; // 16-bit baud generation 
    __delay_ms(5); 
    BRGH = 1; // High baud rate enabled 
    __delay_ms(5); 
    ABDEN = 0; // Auto baud detect disabled 
    __delay_ms(5); 

    // Baud prescaler n = [Fosc/(D*BR)] - 1 

    SPBRGH = _BAUD_PRESCALER_HIGH_; 
    __delay_ms(5); 
    SPBRGL = _BAUD_PRESCALER_LOW_; 
    __delay_ms(5); 

    TRISC6 = 0; // IadjPWM pin configured as output 
    __delay_ms(5); 
    ANSC6 = 0; // IadjPWM pin not analog input 
    __delay_ms(5); 
    TRISA5 = 0; // DimPWM pin configured as output 
    __delay_ms(5); 

    LATC6 = 1; // Max current for now until PWM written 
    __delay_ms(5); 

    while(1){ 

    // Inline assembly code to clear watchdog timer 
    //asm("CLRWDT"); 

    /*if(RXIN == 5){ 
     RA5 = 1; 
    } 
    else{ 
     RA5 = 0; 
    }*/ 

     if(PIR1bits.RCIF){ 
      writeRXIN(UARTRead()); 
      //RA5 = 0; 
      TX(RXIN); 
     } // end if RCIF 

     while(RXIN > 0){ 
      RA5 = 1; 
      __delay_ms(100); 
      RA5 = 0; 
      __delay_ms(100); 
      RXIN--; 
     } 

    } 
    // infinite loop 
    // never leave this loop 

    RA5 = 1; 
    return (EXIT_SUCCESS); 
} // end main 

/*void interrupt ISR(void){ 
    if(RCIF){// if USART Receive interrupt flag 
     RA5 = 1; 

     if(FERR){ 
      flagRXFramingError = 1; 
      SPEN = 0; 
      SPEN = 1; 

     } 
     if(OERR){ 
      flagRXOverrunError = 1; 
      CREN = 0; 
      CREN = 1; 
     } 

     while(RCIF){ // RCIF high as long as there is data in FIFO register. Read RCREG to clear RCIF flag 
      writeRXIN(UARTRead()); 
     } 

     RA5 = 0; 
    } 

    if (TXIF){// if USART Transmit interrupt 
     TXIF = 0; // Clear interrupt flag 
    } 
} // end ISRs*/ 
+1

写入寄存器之间的5ms延迟是完全无意义的。 5毫秒即使在蹩脚的PIC上也是永恒的。这些是片上存储器映射寄存器 - 你根本不需要任何延迟。 (在某些特殊情况下,在为端口I/O设置数据方向后,您可能需要等待几个时钟周期,但这只是关于它。)首先删除所有5ms延迟。 – Lundin

+1

(作为未来参考的一个便笺:虽然这个问题没有问题,但是如果您有关于特定硬件外设的问题,最好在https://electronics.stackexchange.com/上询问,例如在某些PIC上的UART,潜伏在该站点上的许多PIC专家以及微控制器固件问题也完全在此处讨论)。 – Lundin

+0

尽管如此,我不得不赞成这一点,只是为了'已经在示波器上确认信号进入RX并且使用相同波特率在TX引脚之外,所以我认为波特率配置正确(300波特,8N1)。我还在示波器RX引脚上接收到强烈干净的5V信号。我们得到了太多的嵌入式问题,绝对没有任何硬件工作的迹象,因此必须立即下载/关闭/删除投票,因为软件问答网站本质上是无法解析的;( –

回答

0

解决了这个问题

我不知道究竟解决了这个问题,但我会分享我做了重大的变化和新的代码。

  1. 我启用了TXIE。 TXIF几乎总是高电平,所以它会产生连续中断 。我没有看到启用TX中断的原因, 虽然可能是一个很好的。如果要TX等到TXIF 不为零并传输,否则为什么要使用该标志?

  2. 我有中断启用错误的顺序。我应该有 启用外围设备,然后他们的个别中断,如果 必要,然后PEIE,最后是GIE。

  3. 我没有在我的中断中处理FERR和OERR,虽然他们可能会触发并导致中断。

另外我的RXDTSEL在我原来的代码中设置错误。这是新的工作代码。现在它所做的只是回显RX信号,并使LED闪烁指示发送的次数。

#include <stdio.h> 
#include <stdlib.h> 
#include <xc.h> 

// This is for 300 baud rate 
#define _BAUD_PRESCALER_LOW_ 0x2A 
#define _BAUD_PRESCALER_HIGH_ 0x68 
#define _XTAL_FREQ 32000000 
#define _PIN_DIMPWMPIN_ RA5 

#pragma config FOSC = INTOSC // Oscillator Selection->INTOSC oscillator: I/O function on CLKIN pin 
#pragma config WDTE = OFF // Watchdog Timer Enable->WDT enabled 
#pragma config PWRTE = OFF // Power-up Timer Enable->PWRT disabled 
#pragma config MCLRE = OFF // MCLR Pin Function Select->MCLR/VPP pin function is digital input 
#pragma config CP = OFF // Flash Program Memory Code Protection->Program memory code protection is disabled 
#pragma config CPD = OFF // Data Memory Code Protection->Data memory code protection is disabled 
#pragma config BOREN = ON // Brown-out Reset Enable->Brown-out Reset enabled 
#pragma config CLKOUTEN = OFF // Clock Out Enable->CLKOUT function is disabled. I/O or oscillator function on the CLKOUT pin 
#pragma config IESO = OFF // Internal/External Switchover->Internal/External Switchover mode is disabled 
#pragma config FCMEN = OFF // Fail-Safe Clock Monitor Enable->Fail-Safe Clock Monitor is disabled 

// CONFIG2 
#pragma config WRT = OFF // Flash Memory Self-Write Protection->Write protection off 
#pragma config PLLEN = ON // PLL Enable->4x PLL enabled 
#pragma config STVREN = ON // Stack Overflow/Underflow Reset Enable->Stack Overflow or Underflow will cause a Reset 
#pragma config BORV = LO // Brown-out Reset Voltage Selection->Brown-out Reset Voltage (Vbor), low trip point selected. 
#pragma config LVP = OFF 

int flagRXFramingError = 0; 
int flagRXOverrunError = 0; 
volatile unsigned char RXIN = 3; 

unsigned char RX(){ 
    return RCREG; 
} 

void writeRXIN(volatile unsigned char a){ 
    RXIN = a; 
} 

void TX(unsigned char a){ 
    while(!PIR1bits.TXIF); // TXIF is usually 1, only 0 when busy transmitting 
    TXREG = a; 
} 

int main(int argc, char** argv) { 

    // SCS FOSC; SPLLEN disabled; IRCF 8MHz_HF; 
    OSCCON = 0xF0; 
    // TUN 0; 
    OSCTUNE = 0x00; 
    // Set the secondary oscillator 
    // Wait for PLL to stabilize 
    while(OSCSTATbits.PLLR == 0){} 

    ADCON0bits.ADON = 0; 
    ANSELA = 0x00; 
    ANSELB = 0x00; 
    ANSELC = 0x00; 
    PIE1bits.ADIE = 0; // Disable ADC interrupts 

    TRISCbits.TRISC5 = 1; // RX pin set to input 
    TRISCbits.TRISC6 = 0; // IadjPWM pin configured as output 
    TRISAbits.TRISA5 = 0; // DimPWM pin configured as output 

    LATCbits.LATC6 = 1; // Max current for now until PWM written 

    //UART Init 
    BAUDCONbits.BRG16 = 1; // 16-bit baud generation 
    TXSTAbits.BRGH = 1; // High baud rate enabled 
    BAUDCONbits.ABDEN = 0; // Auto baud detect disabled 

    // Baud prescaler n = [Fosc/(D*BR)] - 1 
    SPBRGH = _BAUD_PRESCALER_HIGH_; 
    __delay_ms(1); 
    SPBRGL = _BAUD_PRESCALER_LOW_; 
    __delay_ms(1); 

    APFCON0bits.RXDTSEL = 1; // RX is on RC5 pin 
    APFCON0bits.TXCKSEL = 0; // TX is on RB7 pin 
    TXSTAbits.SYNC = 0; // Asynchronous mode 
    RCSTAbits.SPEN = 1; // Serial Port Enabled 
    RCSTAbits.RX9 = 0; // 8 bit reception 
    TXSTAbits.TX9 = 0; // 8-bit transmission 

    RCSTAbits.CREN = 1; // Receiver enabled 
    TXSTAbits.TXEN = 1; // Transmitter enabled 

    PIE1bits.TXIE = 0; // Enable USART Transmitter interrupt 
    PIE1bits.RCIE = 1; // Enable USART Receive interrupt 
    while(PIR1bits.RCIF){ 
     writeRXIN(RX()); 
    } 

    INTCONbits.PEIE = 1; // Enable peripheral interrupts 
    INTCONbits.GIE = 1; // Enable global interrupts 

    while(1){ 
     while(RXIN > 0){ 
      TX(RXIN); 
      _PIN_DIMPWMPIN_ = 1; 
      __delay_ms(100); 
      _PIN_DIMPWMPIN_ = 0; 
      __delay_ms(100); 
      RXIN--; 
     } 

    } 
    // infinite loop 
    // never leave this loop 
    return (EXIT_SUCCESS); 
} // end main 

void interrupt ISR(void){ 

    if(PIE1bits.RCIE && PIR1bits.RCIF){ // handle RX pin interrupts 
     while(PIR1bits.RCIF){ 
      writeRXIN(RX()); 
     } 
     if(RCSTAbits.FERR){ 
      flagRXFramingError = 1; 
      SPEN = 0; 
      SPEN = 1; 

     } 
     if(RCSTAbits.OERR){ 
      flagRXOverrunError = 1; 
      CREN = 0; 
      CREN = 1; 
     } 
    } // end RX pin interrupt handlers 

} // end ISRs*/ 
+0

我想你现在正在清除外设的任何未决错误(通过重置外设),然后接收器再次开始工作...... –

0

某些微控制器停止接收字节,如果存在某种错误。一定要清除这些错误。通常通过清除一些UART控制寄存器位。