/* This function will write a character to serial without interrupt enable mode */
void rt_serial_putc(const char c)
/* This function will write a character to serial without interrupt enable mode */
void rt_serial_putc(const char c)
{
    if (c=='\n')rt_serial_putc('\r');
    while(!(UTRSTAT0 & USTAT_TXB_EMPTY));
    UTXH0 = (rt_uint8_t)c;
}