Embedded UART RS485 source code works same as uart - JohnHau/mis GitHub Wiki

#include<stdio.h> #include<stdlib.h> #include<string.h> #include<sys/types.h> #include<sys/stat.h> #include<unistd.h> #include<fcntl.h> #include<pthread.h> #include<termios.h> #include<semaphore.h> #include<mqueue.h>

int setopt(int fd) { struct termios newtios,oldtios;

    if(tcgetattr(fd,&oldtios)!= 0)
    {
            perror("tcgetattr failed\n");
            exit(EXIT_FAILURE);
    }


    bzero(&newtios,sizeof(newtios));

    newtios.c_cflag |= CLOCAL | CREAD;
    newtios.c_cflag &= ~CSIZE;
    newtios.c_cflag |= CS8;
    newtios.c_cflag &= ~PARENB;
    newtios.c_cflag &= ~CSTOPB;

    //newtios.c_cflag |= CRTSCTS;
    //newtios.c_iflag = IGNPAR | ICRNL;

    newtios.c_iflag = IGNPAR;
    newtios.c_oflag = 0;
    newtios.c_lflag = 0;

    cfsetispeed(&newtios,B115200);
    cfsetospeed(&newtios,B115200);

    newtios.c_cc[VTIME] = 1;
    newtios.c_cc[VMIN] = 1;


    tcflush(fd,TCIFLUSH);
    tcflush(fd,TCOFLUSH);

    if(tcsetattr(fd,TCSANOW,&newtios) != 0)
    {
            perror("tcsetattr failed\n");
            exit(EXIT_FAILURE);

    }


    return 0;

}

#define UART_NAME "/dev/ttyS7"

int FH_open_uart(const char* name) { int fd;

    if((fd = open(name,O_RDWR)) <0)
    //if((fd = open(name,O_RDONLY | O_NOCTTY)) <0)
    {
            perror("FH_open_uart failed\n");
            exit(EXIT_FAILURE);
    }

    setopt(fd);

    return fd;

}

//command byte //0x40 Read Device Status //function byte //0x15 Read device properties + configCRC

//msgtype device type address dflen checksum //0x00 0x11 0x06 0x03 0x40 0x00 0x15 0x91 static uint8_t Checksum; uint8_t PB_recv_buf[1024] = {0};

int32_t PB_uartSend(int fd,char* pBuf,int len) { uint8_t i = 0; for(i=0;i<len;i++) { Checksum += pBuf[i]; } if(i == len) { Checksum = ~Checksum + 1; pBuf[i] = Checksum & 0xff; }

    //0x00       0x11          0x06     0x03     0x40 0x15      0x91
    uint8_t test[] = {0x00,0x11,0x06,0x03,0x40,0x00,0x15,0x91};
    //uint8_t test[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x10,0x06,0x03,0x40,0x00,0x15,0x92};

    for(i=0;i<sizeof(test);i++)
    {
            printf("send is %2x\n",test[i]);

    }

    //if(write(fd,pBuf,len+1) != (len+1))
    if(write(fd,test,sizeof(test)) != (sizeof(test)))
    {
            perror("PB_uartSend failed\n");
            //exit(EXIT_FAILURE);
            return -1;

    }

// tcflush(fd,TCIOFLUSH);

    return 0;

}

int32_t PB_uartSend_test(int fd) { uint8_t i = 0;

    //0x00       0x11          0x06     0x03     0x40 0x15      0x91
    uint8_t test[] = {0x00,0x11,0x06,0x03,0x40,0x00,0x15,0x91};
    //uint8_t test[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x10,0x06,0x03,0x40,0x00,0x15,0x92};

    for(i=0;i<sizeof(test);i++)
    {
            printf("send is %2x\n",test[i]);

    }

    //if(write(fd,pBuf,len+1) != (len+1))
    //if(write(fd,test,sizeof(test)) != (sizeof(test)))
    if(write(fd,test,8) != 8)
    {
            perror("PB_uartSend failed\n");
            //exit(EXIT_FAILURE);
            return -1;

    }

// tcflush(fd,TCIOFLUSH);

    return 0;

}

int32_t PB_uartRecv(int fd,char* pBuf,int len) { int i = 0;

    i = read(fd,pBuf,128);
    return i;
    for(i=0;i<512;i++)
    {
            printf("reading\n");
            //if(read(fd,pBuf+i,1) <=0)
            if(read(fd,pBuf+i,1) !=1)
            {
                    perror("reading error\n");
                    break;
            }

    }

    return i;

}

uint8_t read_dev_sta__read_dev_property[] = {0x00,0x11,0x06,0x03,0x40,0x00,0x15};

uint8_t in_buffer[256] = {0};

int main(int argc,char* argv[]) { int fd;

    fd = FH_open_uart(UART_NAME);

    if(fd < 0)
    {
            perror("open uart failed\n");
            exit(EXIT_FAILURE);
    }

    printf("fd is %d\n",fd);

#if 1 printf("reading\n"); int n = read(fd,in_buffer,5); printf("n is %d\n",n); printf("in_buffer is %s\n",in_buffer);

    printf("writing\n");
    PB_uartSend_test(fd);
    close(fd);
    return 0;

#endif

#if 0 printf("reading\n"); int n = read(fd,in_buffer,5); printf("n is %d\n",n); printf("in_buffer is %s\n",in_buffer);

    write(fd,in_buffer,n);

#endif

#if 0 //uint8_t tt[] = {0x00,0x11,0x06,0x03,0x40,0x00,0x15}; uint8_t tt[] = {0x00,0x10,0x06,0x03,0x40,0x00,0x15}; uint8_t ck = PB_cal_checksum(tt,sizeof(tt)); printf("ck is %02x\n",ck);

    return 0;

#endif

    close(fd);

    return 0;

}

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