uart.c

LPC23xx_24xx系列ARM的源码实例

/*****************************************************************************
 *   uart.c:  UART API file for NXP LPC23xx/24xx Family Microprocessors
 *
 *   Copyright(C) 2006, NXP Semiconductor
 *   All rights reserved.
 *
 *   History
 *   2006.07.12  ver 1.00    Prelimnary version, first Release
 *
******************************************************************************/
#include "LPC23xx.h"                        /* LPC23xx/24xx definitions */
#include "type.h"
#include "target.h"
#include "irq.h"
#include "uart.h"

volatile DWORD UART0Status, UART1Status;
volatile BYTE UART0TxEmpty = 1, UART1TxEmpty = 1;
volatile BYTE UART0Buffer[BUFSIZE], UART1Buffer[BUFSIZE];
volatile DWORD UART0Count = 0, UART1Count = 0;

/*****************************************************************************
** Function name:		UART0Handler
**
** Descriptions:		UART0 interrupt handler
**
** parameters:			None
** Returned value:		None
** 
*****************************************************************************/
void UART0Handler (void) __irq 
{
    BYTE IIRValue, LSRValue;
    BYTE Dummy = Dummy;

    IENABLE;				/* handles nested interrupt */	
    IIRValue = U0IIR;
    
    IIRValue >>= 1;			/* skip pending bit in IIR */
    IIRValue &= 0x07;			/* check bit 1~3, interrupt identification */
    if ( IIRValue == IIR_RLS )		/* Receive Line Status */
    {
		LSRValue = U0LSR;
		/* Receive Line Status */
		if ( LSRValue & (LSR_OE|LSR_PE|LSR_FE|LSR_RXFE|LSR_BI) )
		{
	    	/* There are errors or break interrupt */
	    	/* Read LSR will clear the interrupt */
	    	UART0Status = LSRValue;
	    	Dummy = U0RBR;		/* Dummy read on RX to clear 
								interrupt, then bail out */
	    	IDISABLE;
	    	VICVectAddr = 0;		/* Acknowledge Interrupt */
	    	return;
		}
		if ( LSRValue & LSR_RDR )	/* Receive Data Ready */			
		{
	    	/* If no error on RLS, normal ready, save into the data buffer. */
	    	/* Note: read RBR will clear the interrupt */
	    	UART0Buffer[UART0Count] = U0RBR;
	    	UART0Count++;
	    	if ( UART0Count == BUFSIZE )
	    	{
				UART0Count = 0;		/* buffer overflow */
	    	}	
		}
    }
    else if ( IIRValue == IIR_RDA )	/* Receive Data Available */
    {
		/* Receive Data Available */
		UART0Buffer[UART0Count] = U0RBR;
		UART0Count++;
		if ( UART0Count == BUFSIZE )
		{
	    	UART0Count = 0;		/* buffer overflow */
		}
    }
    else if ( IIRValue == IIR_CTI )	/* Character timeout indicator */
    {
		/* Character Time-out indicator */
		UART0Status |= 0x100;		/* Bit 9 as the CTI error */
    }
    else if ( IIRValue == IIR_THRE )	/* THRE, transmit holding register empty */
    {
		/* THRE interrupt */
		LSRValue = U0LSR;		/* Check status in the LSR to see if
								valid data in U0THR or not */
		if ( LSRValue & LSR_THRE )
		{
	    	UART0TxEmpty = 1;
		}
		else
		{
	    	UART0TxEmpty = 0;
		}
    }
    
    IDISABLE;
    VICVectAddr = 0;		/* Acknowledge Interrupt */
}

/*****************************************************************************
** Function name:		UART1Handler
**
** Descriptions:		UART1 interrupt handler
**
** parameters:			None
** Returned value:		None
** 
*****************************************************************************/
void UART1Handler (void) __irq 
{
    BYTE IIRValue, LSRValue;
    BYTE Dummy = Dummy;

    IENABLE;				/* handles nested interrupt */	
    IIRValue = U1IIR;
    
    IIRValue >>= 1;			/* skip pending bit in IIR */
    IIRValue &= 0x07;			/* check bit 1~3, interrupt identification */
    if ( IIRValue == IIR_RLS )		/* Receive Line Status */
    {
		LSRValue = U1LSR;
		/* Receive Line Status */
		if ( LSRValue & (LSR_OE|LSR_PE|LSR_FE|LSR_RXFE|LSR_BI) )
		{
	    	/* There are errors or break interrupt */
	    	/* Read LSR will clear the interrupt */
	    	UART1Status = LSRValue;
	    	Dummy = U1RBR;		/* Dummy read on RX to clear 
								interrupt, then bail out */
	    	IDISABLE;
	    	VICVectAddr = 0;		/* Acknowledge Interrupt */
	    	return;
		}
		if ( LSRValue & LSR_RDR )	/* Receive Data Ready */			
		{
	    	/* If no error on RLS, normal ready, save into the data buffer. */
	    	/* Note: read RBR will clear the interrupt */
	    	UART1Buffer[UART1Count] = U1RBR;
	    	UART1Count++;
	    	if ( UART1Count == BUFSIZE )
	    	{
				UART1Count = 0;		/* buffer overflow */
	    	}	
		}
    }
    else if ( IIRValue == IIR_RDA )	/* Receive Data Available */
    {
		/* Receive Data Available */
		UART1Buffer[UART1Count] = U1RBR;
		UART1Count++;
		if ( UART1Count == BUFSIZE )
		{
	    	UART1Count = 0;		/* buffer overflow */
		}
    }
    else if ( IIRValue == IIR_CTI )	/* Character timeout indicator */
    {
		/* Character Time-out indicator */
		UART1Status |= 0x100;		/* Bit 9 as the CTI error */
    }
    else if ( IIRValue == IIR_THRE )	/* THRE, transmit holding register empty */
    {
		/* THRE interrupt */
		LSRValue = U1LSR;		/* Check status in the LSR to see if
								valid data in U0THR or not */
		if ( LSRValue & LSR_THRE )
		{
	    	UART1TxEmpty = 1;
		}
		else
		{
	    	UART1TxEmpty = 0;
		}
    }
    
    IDISABLE;
    VICVectAddr = 0;		/* Acknowledge Interrupt */
}

/*****************************************************************************
** Function name:		UARTInit
**
** Descriptions:		Initialize UART0 port, setup pin select,
**						clock, parity, stop bits, FIFO, etc.
**
** parameters:			portNum(0 or 1) and UART baudrate
** Returned value:		true or false, return false only if the 
**						interrupt handler can't be installed to the 
**						VIC table
** 
*****************************************************************************/
DWORD UARTInit( DWORD PortNum, DWORD baudrate )
{
    DWORD Fdiv;

	if ( PortNum == 0 )
	{
		PINSEL0 = 0x00000050;       /* RxD0 and TxD0 */

    	U0LCR = 0x83;		/* 8 bits, no Parity, 1 Stop bit */
    	Fdiv = ( Fpclk / 16 ) / baudrate ;	/*baud rate */
    	U0DLM = Fdiv / 256;							
    	U0DLL = Fdiv % 256;
		U0LCR = 0x03;		/* DLAB = 0 */
    	U0FCR = 0x07;		/* Enable and reset TX and RX FIFO. */

    	if ( install_irq( UART0_INT, (void *)UART0Handler, HIGHEST_PRIORITY ) == FALSE )
    	{
			return (FALSE);
    	}
   
    	U0IER = IER_RBR | IER_THRE | IER_RLS;	/* Enable UART0 interrupt */
    	return (TRUE);
	}
	else if ( PortNum == 1 )
	{
#if 0
		PINSEL0 |= 0x40000000; /* Enable TxD1 P0.15 */
		PINSEL1 |= 0x00000001; /* Enable RxD1 P0.16	*/
#else
		PINSEL7 |= 0x0000000F;
#endif

    	U1LCR = 0x83;		/* 8 bits, no Parity, 1 Stop bit */
    	Fdiv = ( Fpclk / 16 ) / baudrate ;	/*baud rate */
    	U1DLM = Fdiv / 256;							
    	U1DLL = Fdiv % 256;
		U1LCR = 0x03;		/* DLAB = 0 */
    	U1FCR = 0x07;		/* Enable and reset TX and RX FIFO. */

    	if ( install_irq( UART1_INT, (void *)UART1Handler, HIGHEST_PRIORITY ) == FALSE )
    	{
			return (FALSE);
    	}
   
    	U1IER = IER_RBR | IER_THRE | IER_RLS;	/* Enable UART0 interrupt */
    	return (TRUE);
	}
	return( FALSE ); 
}

/*****************************************************************************
** Function name:		UARTSend
**
** Descriptions:		Send a block of data to the UART 0 port based
**						on the data length
**
** parameters:			portNum, buffer pointer, and data length
** Returned value:		None
** 
*****************************************************************************/
void UARTSend( DWORD portNum, BYTE *BufferPtr, DWORD Length )
{
	if ( portNum == 0 )
	{
    	while ( Length != 0 )
    	{
			/* THRE status, contain valid data */
			while ( !(UART0TxEmpty & 0x01) );	
			U0THR = *BufferPtr;
			UART0TxEmpty = 0;	/* not empty in the THR until it shifts out */
			BufferPtr++;
			Length--;
		}
    }
	else
	{
		while ( Length != 0 )
    	{
			/* THRE status, contain valid data */
			while ( !(UART1TxEmpty & 0x01) );	
			U1THR = *BufferPtr;
			UART1TxEmpty = 0;	/* not empty in the THR until it shifts out */
			BufferPtr++;
			Length--;
    	}
	}
    return;
}

/******************************************************************************
**                            End Of File
******************************************************************************/