False positives of uart interrupts?

Question

Microcontrollers

Faced the problem of "false" interrupts on receiving uart lpc11uxx. As if "false" in quotes, because perhaps a misconfiguration

The code:

void uart_sc_mode(void) {
  LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 12);
  LPC_SYSCON->UARTCLKDIV &= ~0xff;
  LPC_SYSCON->UARTCLKDIV |= 0x01;
  
  LPC_IOCON->PIO0_19 &= ~(0x7f 			// clear 0-6 bits
                    | (1 << 10));		// clear 10 bit
  LPC_IOCON->PIO0_19 |= (1 << 0)		// TXD mode
                    | (1 << 10);		// Open-drain mode
  
/*	LPC_IOCON->PIO0_18 &= ~(0x7f			// clear 0-6 bits
                    | (1 << 10));   // clear 10 bit
  LPC_IOCON->PIO0_18 |= (1 << 0) 		// RXD mode
                    | (1 << 10);		// Open-drain mode*/
  
  LPC_IOCON->PIO0_17 &= ~(0x7f			// clear 0-6 bits
                    | (1 << 10));		// clear 10 bit
  LPC_IOCON->PIO0_17 |= 0x03;       // SCLK mode
  
  LPC_USART->SCICTRL |= 0x01;				// Asynchronous half-duplex sc interface enable
  LPC_USART->SCICTRL &= ~(3 << 1);	// A NACK response is inhibited; T = 0
  
  uart_sc_mode_config(SystemFrequency, 3570000, 372);
  
  LPC_USART->IER = IER_RBR | IER_RLS;
              
}

void uart_sc_mode_config(uint32_t sys_clk, uint32_t Freq, uint32_t scale) {
  uint32_t divider = ( ( ( sys_clk * 2 ) / Freq ) + 1 ) >> 1;
  
  NVIC_DisableIRQ(UART_IRQn);
  
  LPC_USART->LCR &= ~0x9f;
  LPC_USART->LCR |= ( 3 << 0 )	// 8 bit
                | ( 0 << 2 )		// 1 stop bit
                | ( 1 << 3 )		// parity enable
                | ( 1 << 4 )		// even parity
                | ( 1 << 7 ); 	// DLAB = 1
  
  LPC_USART->DLL &= ~0xff;
  LPC_USART->DLM &= ~0xff;
  
  LPC_USART->DLM = ( divider >> 8 ) & 0xff;	
  LPC_USART->DLL = divider & 0xff;
    
  LPC_USART->LCR &= ~( 1 << 7 );	// DLAB = 0
  
  LPC_USART->FCR |= ( 1 << 0 ) 	// enable access to the other field in register
                | ( 1 << 1 )		// enable and clear RxBuff
                | ( 1 << 2 )		// enable and clear TxBuff
                | ( 0 << 6 ); 	// interrupt after every recieve byte
  
  LPC_USART->OSR &= ~( 0x3fff );
  LPC_USART->OSR = ( scale - 1 ) << 4;
  
  LPC_USART->SCICTRL &= ~( ( 0xff << 8 ) | ( 0x07 << 5 ) );
  LPC_USART->SCICTRL |= ( 0xff << 8 ) | ( 0x07 << 5 );
  
  NVIC_EnableIRQ(UART_IRQn);
} 

void 
UART_IRQHandler( void ) 
{
  timer0_stop();
  timer0_reset();
  if ( ( LPC_USART->IIR >> 1 ) & IIR_RDA )	{
    g_UartMsg.buffer[g_UartMsg.byteCount++] = LPC_USART->RBR;
  }
  timer0_start(TIMEOUT_DEFAULT_BYTE, g_etu2ticks);
}