Hands-On RTOS with Microcontrollers

startReceiveInt

The startReceiveInt function is very similar to the one used for the queue-based driver:

static bool rxInProgress = false;static uint_fast16_t rxLen = 0;static uint8_t* rxBuff = NULL;static uint_fast16_t rxItr = 0;int32_t startReceiveInt( uint8_t* Buffer, uint_fast16_t Len ){    if(!rxInProgress && (Buffer != NULL))    {        rxInProgress = true;        rxLen = Len;        rxBuff = Buffer;        rxItr = 0;        USART2->CR3 |= USART_CR3_EIE; //enable error interrupts        USART2->CR1 |= (USART_CR1_UE | USART_CR1_RXNEIE);        NVIC_SetPriority(USART2_IRQn, 6);        NVIC_EnableIRQ(USART2_IRQn);        return 0;    }    return -1;}

Here are the notable differences in this setup:

• This variant takes in a pointer to a buffer (Buffer), as well as the desired length of the transfer (Len). A couple ...