Windows XP

• nbtstat
• arp

Fedora

• arp
• nbtscan

예제 (TCN75)

I2C 인터페이스인 TCN75 칩의 온도를 가져오기 위한 응용이다.

...
#define I2C_ADDR_TCN75 0x4f  // 하드웨어 설계에 따라 달라진다.
...

void tcn75_init(void)
{
    int fd;

    fd = open("/dev/i2c-0", O_RDWR); // mknod /dev/i2c-0 c 89 0
    if(fd < 0) {
        fprintf(stderr, "can't open /dev/i2c-0\n");
        exit(2);
    }

    ioctl(fd, I2C_SLAVE, I2C_ADDR_TCN75);

    unsigned char cmd, read_data[2];
    int read_value;
    cmd = 0x00; // TEMP
    write(fd, &cmd, 1); // Pointer Byte
    close(fd);
}

float tcn75_get_temperature(void)
{
    int fd;

    fd = open("/dev/i2c-0", O_RDWR);
    if(fd < 0) {
        fprintf(stderr, "can't open /dev/i2c-0\n");
        exit(2);
    }

    ioctl(fd, I2C_SLAVE, I2C_ADDR_TCN75);

    unsigned char read_data[2];
    int read_value;
    float temperature;
    read(fd, read_data, 2);
    read_value = (read_data[0]<<8) | read_data[1];
    read_value >>= 7;
    if(read_value > 256) read_value = read_value - 512;
    temperature = read_value / 2.0;
    close(fd);
    return temperature;
}


int main(int argc, char** argv)
{
    tcn75_init();
    while(1) {
        printf("temp = %f\n", tcn75_get_temperature());
        sleep(1);
    }
    return 0;
}

// 유닉스타임스탬프를 인자로 주면 현재일시를 스트링으로 반환한다.
char* from_unixtime(time_t unix_timestamp)
{
    static char szDatetime[25];
    struct tm *tm_infop;
    tm_infop = localtime(&unix_timestamp);
    memcpy(szDatetime, asctime(tm_infop), 24);
    szDatetime[24] = '\0';
    return szDatetime;
}

#define POLY 0x8408
/*
//                                      16   12   5
// this is the CCITT CRC 16 polynomial X  + X  + X  + 1.
// This works out to be 0x1021, but the way the algorithm works
// lets us use 0x8408 (the reverse of the bit pattern).  The high
// bit is always assumed to be set, thus we only use 16 bits to
// represent the 17 bit value.
*/

UINT16 CCITT_CRC16(char *data_p, UINT16 length)
{
    unsigned char i;
    unsigned int data;
    unsigned int crc = 0xffff;

    if (length == 0)
        return (~crc);

    do
    {
        for (i=0, data=(unsigned int)0xff & *data_p++;i < 8; 
                i++, data >>= 1)
        {
            if ((crc & 0x0001) ^ (data & 0x0001))
                crc = (crc >> 1) ^ POLY;
            else  crc >>= 1;
        }
    } while (--length);

    crc = ~crc;
    data = crc;
    crc = (crc << 8) | ((data >> 8) & 0xff);

    return (crc);
}