void InitUart(void)
{
    //отключаем пины USART0
    AT91C_BASE_PIOA->PIO_PDR = PA1 | PA0;


    AT91C_BASE_SYS->AIC_SVR[AT91C_ID_US0] = (INT32U) UartIrqHandler;
    //растановка приоритета прерывания
    AT91C_BASE_SYS->AIC_SMR[AT91C_ID_US0] = 0x63; // SRCTYPE=1, PRIOR=3. USART 0 interrupt positive edge-triggered at prio 3 //0x02;
    //разрешение прерывания по Timer 1
    AT91C_BASE_SYS->AIC_IECR = (1<<AT91C_ID_US0);
    AT91C_BASE_SYS->AIC_ICCR = (1<<AT91C_ID_US0);


    *AT91C_US0_BRGR = 625;
    *AT91C_US0_MR = 0x000808C0; // Normal mode, 1 stop bit, no parity, async mode, 8 bits, MCK.
    *AT91C_US0_IDR = 0xffffffff; // Disable all USART interrupts
    *AT91C_US0_IER = AT91C_US_RXRDY;

    *AT91C_US0_CR = AT91C_US_RXDIS | AT91C_US_TXDIS;
    *AT91C_US0_CR = 0x0000010c; // Reset status bits, reset rx/tx.
    *AT91C_US0_CR = AT91C_US_RXEN | AT91C_US_TXEN;
    *AT91C_PMC_PCER = (1 << AT91C_ID_US0);
}

void UartIrqHandler(void)
{
    INT8U Tmp = *AT91C_US0_CSR;
    INT8U Data;

    //AT91C_BASE_AIC->AIC_IVR = 0;
    //AT91C_BASE_AIC->AIC_ICCR  = (1 << AT91C_ID_US0);

    Data = *AT91C_US0_RHR;

    do
    {
        Tmp = *AT91C_US0_CSR;
    } while ((Tmp & 0x02) == 0);

    *AT91C_US0_THR = Data;

    Main.Led1Blink = 1;
    
    AT91C_BASE_AIC->AIC_EOICR = 0;            // Signal end of interrupt
}