ARM, RISC-V контроллеры

void UART2setup(void)
{
	RCC->APB1PCENR |= RCC_USART2EN;
	USART2->CTLR2 =(uint16_t)0;
	USART2->CTLR1 =(uint16_t)0;
	USART2->CTLR3 =(uint16_t)0;
	USART2->CTLR1 =USART_Enable|USART_Mode_Rx|USART_Mode_Tx|USART_IT_RXDNE;
	USART2->BRR = (uint16_t)baudesRate115200;
	NVIC_EnableIRQ(USART2_IRQn);
	UARTcommandDataBuffer[0]=(uint8_t)1;
}
void USART2_IRQHandler(void)
{
	uint8_t tmp;
	static int status;
	USART2->STATR&=~USART_STATR_RXNE;
	tmp=USART2->DATAR;

	if (tmp!=(uint8_t)0x0d)
	{
		if (tmp!=(uint8_t)0x0a)
		{
			UARTcommandDataBuffer[UARTcommandDataBuffer[0]++]=tmp;
			if(UARTcommandDataBuffer[0]>=((sizeof UARTcommandDataBuffer)/(sizeof UARTcommandDataBuffer[0])))
			{
				UARTcommandDataBuffer[0]=(uint8_t)0xf;
				status=(int)-1;
			}
			else
			{
				status=(int)0;
			}
		}
	}
	else
	{
		UARTcommandDataBuffer[UARTcommandDataBuffer[0]++]=tmp;
		if(status==0)
		{
			UARTstringReady=UARTcommStatusReady;
		}
		else
		{
			UARTstringReady=UARTcommStatusError;
		}
	}
}