/**
* Get a full configuration of the UART.
**/
static BT_ERROR uartGetConfig(BT_HANDLE hUart, BT_UART_CONFIG *pConfig) {
volatile LM3Sxx_UART_REGS *pRegs = hUart->pRegs;
pConfig->eMode = hUart->eMode;
BT_ERROR Error = BT_ERR_NONE;
BT_u32 ulInputClk = BT_LM3Sxx_GetSystemFrequency();
// Compute the baud rate.
pConfig->ulBaudrate = (ulInputClk * 4) / ((64 * pRegs->IBRD) + pRegs->FBRD);
pConfig->ulTxBufferSize = BT_FifoSize(hUart->hTxFifo);
pConfig->ulRxBufferSize = BT_FifoSize(hUart->hRxFifo);
pConfig->ucDataBits = ((pRegs->LCRH >> 5) & 0x00000003) + 5;
pConfig->ucStopBits = ((pRegs->LCRH >> 3) & 0x00000001) + 1;
if ((pRegs->LCRH & 0x00000086) == LM3Sxx_UART_LCRH_EVEN) pConfig->ucParity = BT_UART_PARITY_EVEN;
else if ((pRegs->LCRH & 0x00000086) == LM3Sxx_UART_LCRH_MARK) pConfig->ucParity = BT_UART_PARITY_MARK;
else if ((pRegs->LCRH & 0x00000086) == LM3Sxx_UART_LCRH_SPACE) pConfig->ucParity = BT_UART_PARITY_SPACE;
else if ((pRegs->LCRH & 0x00000086) == LM3Sxx_UART_LCRH_ODD) pConfig->ucParity = BT_UART_PARITY_ODD;
else pConfig->ucParity = BT_UART_PARITY_NONE;
pConfig->eMode = hUart->eMode;
return Error;
}
static BT_ERROR uartSetBaudrate(BT_HANDLE hUart, BT_u32 ulBaudrate) {
volatile LM3Sxx_UART_REGS *pRegs = hUart->pRegs;
BT_u32 ulInputClk;
BT_u32 BaudRate = ulBaudrate;
/*
* We must determine the input clock frequency to the UART peripheral.
*/
ulInputClk = BT_LM3Sxx_GetSystemFrequency();
uartDisable(hUart);
/*
* Determine the Baud divider. It can be 4to 254.
* Loop through all possible combinations
*/
// Is the required baud rate greater than the maximum rate supported
// without the use of high speed mode?
if((BaudRate * 16) > ulInputClk) {
// Enable high speed mode.
pRegs->CTL |= LM3Sxx_UART_CTL_HSE;
// Half the supplied baud rate to compensate for enabling high speed
// mode. This allows the following code to be common to both cases.
BaudRate /= 2;
}
else {
// Disable high speed mode.
pRegs->CTL &= ~(LM3Sxx_UART_CTL_HSE);
}
// Compute the fractional baud rate divider.
BT_u32 ulDiv = (((ulInputClk * 8) / BaudRate) + 1) / 2;
// Set the baud rate.
pRegs->IBRD = ulDiv / 64;
pRegs->FBRD = ulDiv % 64;
// Start the UART.
uartEnable(hUart);
return BT_ERR_NONE;
}
static BT_u32 LM3Sxx_get_cpu_clock_frequency() {
return BT_LM3Sxx_GetSystemFrequency();
}
