/* Enables or disables the transmitter of an USART peripheral.  */
void USART_SetTransmitterEnabled(AT91S_USART *usart, unsigned char enabled)
/* Enables or disables the transmitter of an USART peripheral.  */
void USART_SetTransmitterEnabled(AT91S_USART *usart, unsigned char enabled)
{
    if (enabled) {
        usart->US_CR = AT91C_US_TXEN;
    }
    else {
        usart->US_CR = AT91C_US_TXDIS;
    }
}