uart0.c

自己编写的飞利浦LPC2200的串口驱动,可以支持在OS下和非OS下,主要通过在.h档下配置实现

#define _UART0_C_

#include "Queue.h"
#include "UART0.h"

static volatile uint8 sendQSemPendFlag = 0;
static volatile uint8 ReceiveQSemPendFlag = 0;
static QUEUE UART0SendQ;
static QUEUE UART0ReceiveQ;
static QUEUE_TYPE UART0SendQBuf[UART0_SENDQ_LENGTH];
static QUEUE_TYPE UART0ReceiveQBuf[UART0_Receive_LENGTH];

uint8 UART0_Init(uint32 baud, uint8 dataBits, uint8 parityCheck, uint8 stopBits)
{
	uint8 err;
	
	UART0_SemCreate(UART0SendSem, 1, &err);
	if(err == 0)
	{
		UART0_SemCreate(UART0ReceiveSem, 1, &err);
		if(err == 0)
		{
			UART0_SemCreate(UART0SendQSem, 0, &err);
			if(err == 0)
			{
				UART0_SemCreate(UART0ReceiveQSem, 0, &err);
				if(err == 0 && 
					QueueInit(&UART0SendQ, UART0SendQBuf, UART0_SENDQ_LENGTH) == QRET_OK &&
					QueueInit(&UART0ReceiveQ, UART0ReceiveQBuf, UART0_Receive_LENGTH) == QRET_OK)
				{
    				PINSEL0 = (PINSEL0 & 0xfffffff0) | 0x05;    /* 选择管脚为UART0 */
					UART0_Setup(baud, dataBits, parityCheck, stopBits);
					U0FCR = 0x07;
					U0IER = 0x01;
					
					return 1;
				}
			}
		}
	}

	return 0;
}

void UART0_Setup(uint32 baud, uint8 dataBits, uint8 parityCheck, uint8 stopBits)
{
	uint16 fdiv;
	uint8 value = 0;

	fdiv = (uint16)(Fpclk/16/baud);
	
	U0LCR |= 0x80;
	U0DLM = (uint8)(fdiv >> 8);
	U0DLL = (uint8)fdiv;
	U0LCR &= ~0x80;

	switch(dataBits)
	{
		case 5:
			value |= 0x00;
			break;
		case 6:
			value |= 0x01;
			break;
		case 7:
			value |= 0x02;
			break;
		case 8:
		default:
			value |= 0x03;
			break;
	}

	if(stopBits == 2)
	{
		value |= (0x01 << 2);
	}

	switch(parityCheck)
	{
		case NO_PARITY:
			value |= (0x00 << 3);
			break;
		case ODD:
			value |= (0x04 << 3);
			break;
		case EVEN:
			value |= (0x05 << 3);
			break;
		case FORCE_0:
			value |= (0x07 << 3);
			break;
		case FORCE_1:
			value |= (0x06 << 3);
			break;
		default:
			value |= (0x00 << 3);
			break;
	}

	U0LCR = (U0LCR & 0xc0) | value;
}

static void UART0_PutChar(uint8 data)
{
	while(QueueIn(&UART0SendQ, data) == QRET_FULL)
	{
		sendQSemPendFlag = 1;
		UART0_SemPend(UART0SendQSem);
	}
	U0IER |= 0x02;
}

static uint8 UART0_GetChar(void)
{
	uint8 data;
	
    while(QueueOut(&UART0ReceiveQ, &data) == QRET_EMPTY)
    {
		ReceiveQSemPendFlag = 1;
        UART0_SemPend(UART0ReceiveQSem);
    }

	return data;
}


void UART0_Send(uint8 *buf, uint32 nBytes)
{
	UART0_SemPend(UART0SendSem);
	while((nBytes--) > 0)
	{
		UART0_PutChar(*(buf++));
	}
	UART0_SemPost(UART0SendSem);
}


void UART0_Receive(uint8 *buf, uint32 nBytes)
{
	UART0_SemPend(UART0ReceiveSem);
	while((nBytes--) > 0)
	{
		*(buf++) = UART0_GetChar();
	}
	UART0_SemPost(UART0ReceiveSem);
}

void UART0_IntService(void)
{
    uint8 IIR, data, i;
    
    UART0_EnterCritical();
    while(((IIR = U0IIR) & 0x01) == 0)
    {
        switch(IIR & 0x0e)
        {
            case 0x02:									/*-->THRE中断*/
                for(i = 0; i < 16; i++)
                {
                    if(QueueOut(&UART0SendQ, &data) == QRET_OK)
                    {
                        U0THR = data;
                    }
                    else
                    {
                        U0IER  &= ~0x02;				/*队列空则停止发送，禁止THRE中断*/
						break;
                    }
                }

				if(sendQSemPendFlag == 1)
				{
					sendQSemPendFlag = 0;
					UART0_SemPost(UART0SendQSem);		/*通知发送任务队列有位置放数据*/
				}
                break;
            case 0x04:									/*-->接收数据可用(RDA)*/
            case 0x0c:                                  /*-->字符超时指示(CTI)*/
				data = U0RBR;
				while(QueueIn(&UART0ReceiveQ, data) == QRET_FULL)
				{
					QueueOut(&UART0ReceiveQ, &i);	/*队列满则丢弃最旧的数据*/
				}
				
				if(ReceiveQSemPendFlag == 1)
				{
					ReceiveQSemPendFlag = 0;
					UART0_SemPost(UART0ReceiveQSem);
				}
                break;
            case 0x06:                                  /* -->接收线状态(RLS)*/
                data = U0LSR;
                break;
            default:
                break;
        }
    } 
	
    VICVectAddr = 0;
    UART0_ExitCritical();
}