lpc_uart.c

给大家提供一个在inram/exram中调试的示例,在周公的lpc2200上调试过.

/***********************************************************************
 *         BU MMS China, Philips Semiconductor Software Support
 *         Embest info&Tech Co. Software Support
 *---------------------------------------------------------------------------
 * The software is delivered "AS IS" without warranty or condition of any
 * kind, either express, implied or statutory.  Everybody can use it as 
 * it is opened and without copyright. We will not take any law responsibility
 * for any problem produced by using this software.
 *---------------------------------------------------------------------------                                                  
 *    File name: 	LPC_Uart.c
 *    Description: 	Define API for UART
 *                                                                                      
 *    History:                                                                     
 *    1. Date: 		Jul 13, 2004                                              
 *       Author: 	Shawn Zhang                                                    
 *       Description: Create  
 *
 *    2. Date: 		Aug 09, 2004                                              
 *       Author: 	Shawn Zhang                                                    
 *       Description: Integrate two method :- by polling and by interrupt, user 
 *		 		could select it.
 *
 *    3. Date: 		Aug 17, 2004                                              
 *       Author: 	Shawn Zhang                                                    
 *       Description: 1) Repair the bug about Tx ring buffer.
 *	 	              2) Repair the bug about ReadTxBuf function and ISR.
 *
 *	4. Date: 		Oct 29, 2004                                              
 *       Author: 	Shawn Zhang                                                    
 *       Description: 1) Use LPC_UartChannel_t struct
 *				2) Modify the interrupt receive characters mechanism
 *	 	              3) Repair some bugs and optimize the code
 *
 *	$Revision: 1.0 $
 **********************************************************************/

#include "LPC_Uart.h"

// Globe variable
LPC_Uart_Config_t Uart0Config, Uart1Config;

/*************************************************************************
 * Function Name: UART_InitUartBuf
 * Parameters: LPC_Uart_Buffer_t *pUartBuf
 * Return: void
 *
 * Description: Initialize Rx & Tx buffer, which is used when adopting interrupt method
 *  
 *************************************************************************/
static void UART_InitUartBuf (LPC_Uart_Buffer_t *pUartBuf)
{
	int i;

	for(i=0; i<UART_RXBUFSIZE; i++)
		pUartBuf->RxBuf[i] = 0;
	
	for(i=0; i<UART_TXBUFSIZE; i++)
		pUartBuf->TxBuf[i] = 0;

	pUartBuf->RxHeadPoint=0;
	pUartBuf->RxTailPoint=0;
	
	pUartBuf->TxHeadPoint=0;
	pUartBuf->TxTailPoint=0;

	pUartBuf->RxCount=0;
	pUartBuf->TxCount=0;

	pUartBuf->RxFlag=0;
}
							
/*************************************************************************
 * Function Name: UART_Init
 * Parameters: 	LPC_Uart_Channel_t DevNum
 *				unsigned long BaudRate
 *				LPC_Uart_WordLenth_t WordLenth
 *				bool TwoStopBitsSelect
 *				bool ParityEnable;
 *				LPC_Uart_ParitySelect_t ParitySelect
 *				bool BreakEnable
 *				bool FIFOEnable
 *				int FIFORxTriggerLevel
 *				bool IntEnable	
 *				unsigned long IntType
 * 			
 * Return: int 
 *             	0: sucess
 *			1: fail
 * Description: Initialize Uart, configure baut rate, frame format and FIFO
 *  
 *************************************************************************/
int UART_Init (LPC_Uart_Channel_t DevNum, unsigned long BaudRate, 
		LPC_Uart_WordLenth_t WordLenth, bool TwoStopBitsSelect, 
		bool ParityEnable, LPC_Uart_ParitySelect_t ParitySelect, 
		bool BreakEnable, bool FIFOEnable, LPC_Uart_FIFORxTriggerLevel_t FIFORxTriggerLevel,
		bool IntEnable, unsigned long IntType)
{
	unsigned long Divisor, Frame, FIFO;
	LPC_Uart_Config_t *pConfig;

	if ( DevNum == UART0 )
		pConfig = &Uart0Config;
	else if (DevNum == UART1)
		pConfig = &Uart1Config;
	else
		return 1;

	// Valid Check
	if ((BaudRate == 0) || (BaudRate > BD115200))
		return 0;
	
	// Copy parameter to global variable
	pConfig->BaudRate = BaudRate;
	pConfig->WordLenth = WordLenth;
	pConfig->TwoStopBitsSelect = TwoStopBitsSelect;
	pConfig->ParityEnable = ParityEnable;
	
	pConfig->BreakEnable = BreakEnable;
	pConfig->FIFOEnable = FIFOEnable;
	
	pConfig->IntEnable = IntEnable;

	// baut rate
	Divisor = (SYS_GetFpclk() >>4) / BaudRate; // Divisor = pclk / (16*bautrate)

	// frame format
	Frame = WordLenth;
	if ( TwoStopBitsSelect )
		Frame |= ( 1<<LCR_STOPBITSEL_BIT );
	if ( ParityEnable )
	{
		pConfig->ParitySelect = ParitySelect;
		Frame |= ( 1<<LCR_PARITYENBALE_BIT );
		Frame |= ( ParitySelect<<LCR_PARITYSEL_BIT );
	}
	if ( BreakEnable )
		Frame |= ( 1<<LCR_BREAKCONTROL_BIT );

	// FIFO
	if ( FIFOEnable )
	{
		pConfig->FIFORxTriggerLevel = FIFORxTriggerLevel;
		FIFO = ((FIFORxTriggerLevel & 0x3)<<6) | 0x1;
	}
		
	// Method Mode
	if ( IntEnable )
	{
		pConfig->IntType = IntType;
		UART_InitUartBuf (&pConfig->UartBuffer);
	}
	
	if ( DevNum == UART0 )
	{
		/* Set baut rate */
		UART0_LCR |= (1<<LCR_DLAB_BIT);		// DLAB = 1
		UART0_DLM = Divisor>>8;
		UART0_DLL = Divisor & 0xff;

		/* Set frame format */
		UART0_LCR = Frame;		// DLAB =0

		/* Set FIFO */
		UART0_FCR = FIFO;

		/* Set Interrupt Enable Register */
		UART0_IER = IntType & 0x7;

		/* Enable TxD0 and RxD0, bit 0~3=0101 */
		PINSEL0 &= ~0xF;
		PINSEL0 |= 0x5;
	}
	else // UART1
	{
		/* Set baut rate */
		UART1_LCR |= (1<<LCR_DLAB_BIT);		// DLAB = 1
		UART1_DLM = Divisor>>8;
		UART1_DLL = Divisor & 0xff;

		/* Set frame format */
		UART1_LCR = Frame;		// DLAB =0

		/* Set FIFO */
		UART1_FCR = FIFO;

		/* Set Interrupt Enable Register */
		UART1_IER = IntType & 0x7;

		/* Enable TxD0 and RxD0, bit 16~19=0101 */
		PINSEL0 &= ~0xF0000;
		PINSEL0 |= 0x50000;
	}
	
	return 0;
}

/*************************************************************************
 * Function Name: UART_PutCharByPolling
 * Parameters: LPC_UartChannel_t DevNum
 * 			 char ch
 * Return: void 
 *
 * Description: Send character by polling LSR register
 *  
 *************************************************************************/
static void UART_PutCharByPolling (LPC_Uart_Channel_t DevNum, char ch)
{
	if ( DevNum == UART0 )
	{
		while(!(UART0_LSR & (1<<LSR_THRE_BIT)));
		UART0_THR = ch;
	}
	else		// UART1
	{
		while(!(UART1_LSR & (1<<LSR_THRE_BIT)));
		UART1_THR = ch;
	}
}

/*************************************************************************
 * Function Name: UART_PutStringByPolling
 * Parameters: LPC_UartChannel_t DevNum
 * 			 char *Buf
 * Return:  int : send character count
 *
 * Description: Send a string by using polling method 
 *  
 *************************************************************************/
int UART_PutStringByPolling(LPC_Uart_Channel_t DevNum, char *Buf)
{
	char *pBuf = Buf ;
	int SendCount = 0;

	while (*pBuf)
	{
		UART_PutCharByPolling(DevNum, *pBuf++);
		++SendCount;
	}

	return SendCount;
}

/*************************************************************************
 * Function Name: UART_GetCharByPolling
 * Parameters: LPC_UartChannel_t DevNum
 * Return: char 
 *
 * Description: Receive a character from Uart by polling LSR register
 *  
 *************************************************************************/
static char UART_GetCharByPolling (LPC_Uart_Channel_t DevNum)
{
	if ( DevNum == UART0 )
	{
		  while (!(UART0_LSR & (1<<LSR_RDR_BIT)));
		  return (UART0_RBR);
	}
	else		//UART1
	{
		  while (!(UART1_LSR & (1<<LSR_RDR_BIT)));
		  return (UART1_RBR);
	}
}

/*************************************************************************
 * Function Name: UART_PutStringByInterrupt
 * Parameters: LPC_UartChannel_t DevNum
 *			  char *Buf
 * Return: int : send character count
 *
 * Description: Send a string into Uart Buffer. 
 * 			Then Uart will send buffer data in its IRQ subroutine.
 *  
 *************************************************************************/