UART_CTL_BITSPERSYM_SHIFT
ctl |= (0 << UART_CTL_BITSPERSYM_SHIFT);
ctl |= (1 << UART_CTL_BITSPERSYM_SHIFT);
ctl |= (2 << UART_CTL_BITSPERSYM_SHIFT);
ctl |= (3 << UART_CTL_BITSPERSYM_SHIFT);
#define UART_CTL_BITSPERSYM_MASK (0x3 << UART_CTL_BITSPERSYM_SHIFT)