/****************************************************************************
 *   $Id:: uart.c 5751 2010-11-30 23:56:11Z usb00423                        $
 *   Project: NXP LPC17xx UART example
 *
 *   Description:
 *     This file contains UART code example which include UART initialization, 
 *     UART interrupt handler, and APIs for UART access.
 *
 ****************************************************************************
 * Software that is described herein is for illustrative purposes only
 * which provides customers with programming information regarding the
 * products. This software is supplied "AS IS" without any warranties.
 * NXP Semiconductors assumes no responsibility or liability for the
 * use of the software, conveys no license or title under any patent,
 * copyright, or mask work right to the product. NXP Semiconductors
 * reserves the right to make changes in the software without
 * notification. NXP Semiconductors also make no representation or
 * warranty that such application will be suitable for the specified
 * use without further testing or modification.
 ****************************************************************************/
#include "uart.h"

#include <LPC17xx.h>
#include <stdint.h>

#define IER_RBR		0x01
#define IER_THRE	0x02
#define IER_RLS		0x04

#define IIR_PEND	0x01
#define IIR_RLS		0x03
#define IIR_RDA		0x02
#define IIR_CTI		0x06
#define IIR_THRE	0x01

#define LSR_RDR		0x01
#define LSR_OE		0x02
#define LSR_PE		0x04
#define LSR_FE		0x08
#define LSR_BI		0x10
#define LSR_THRE	0x20
#define LSR_TEMT	0x40
#define LSR_RXFE	0x80

#define BUFSIZE		0x40

#define TRUE 1
#define FALSE 0

volatile uint32_t UART0Status, UART1Status;
volatile uint8_t UART0TxEmpty = 1, UART1TxEmpty = 1;

/*****************************************************************************
** Function name:		UARTInit
**
** Descriptions:		Initialize UART 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
** 
*****************************************************************************/
uint32_t uart_init( uint32_t PortNum, uint32_t baudrate )
{
  uint32_t Fdiv;
  uint32_t pclkdiv, pclk;

	SystemCoreClockUpdate();

	uint32_t SystemFrequency = SystemCoreClock;

  if ( PortNum == 0 )
  {
	LPC_PINCON->PINSEL0 &= ~0x000000F0;
	LPC_PINCON->PINSEL0 |= 0x00000050;  /* RxD0 is P0.3 and TxD0 is P0.2 */
	/* By default, the PCLKSELx value is zero, thus, the PCLK for
	all the peripherals is 1/4 of the SystemFrequency. */
	/* Bit 6~7 is for UART0 */
	pclkdiv = (LPC_SC->PCLKSEL0 >> 6) & 0x03;
	switch ( pclkdiv )
	{
	  case 0x00:
	  default:
		pclk = SystemFrequency/4;
		break;
	  case 0x01:
		pclk = SystemFrequency;
		break; 
	  case 0x02:
		pclk = SystemFrequency/2;
		break; 
	  case 0x03:
		pclk = SystemFrequency/8;
		break;
	}

    LPC_UART0->LCR = 0x83;		/* 8 bits, no Parity, 1 Stop bit */
		Fdiv = ( pclk / 16 ) / baudrate ;	/*baud rate */
    LPC_UART0->DLM = Fdiv / 256;							
    LPC_UART0->DLL = Fdiv % 256;
		LPC_UART0->LCR = 0x03;		/* DLAB = 0 */
    LPC_UART0->FCR = 0b111;		/* Enable and reset TX and RX FIFO. */

		//   	NVIC_EnableIRQ(UART0_IRQn);

    //LPC_UART0->IER = IER_RBR | IER_THRE | IER_RLS;	/* Enable UART0 interrupt */
    return (TRUE);
  }
  else if ( PortNum == 1 )
  {
	LPC_PINCON->PINSEL4 &= ~0x0000000F;
	LPC_PINCON->PINSEL4 |= 0x0000000A;	/* Enable RxD1 P2.1, TxD1 P2.0 */
	
	/* By default, the PCLKSELx value is zero, thus, the PCLK for
	all the peripherals is 1/4 of the SystemFrequency. */
	/* Bit 8,9 are for UART1 */
	pclkdiv = (LPC_SC->PCLKSEL0 >> 8) & 0x03;
	switch ( pclkdiv )
	{
	  case 0x00:
	  default:
		pclk = SystemFrequency/4;
		break;
	  case 0x01:
		pclk = SystemFrequency;
		break; 
	  case 0x02:
		pclk = SystemFrequency/2;
		break; 
	  case 0x03:
		pclk = SystemFrequency/8;
		break;
	}

    LPC_UART1->LCR = 0x83;		/* 8 bits, no Parity, 1 Stop bit */
	Fdiv = ( pclk / 16 ) / baudrate ;	/*baud rate */
    LPC_UART1->DLM = Fdiv / 256;							
    LPC_UART1->DLL = Fdiv % 256;
	LPC_UART1->LCR = 0x03;		/* DLAB = 0 */
    LPC_UART1->FCR = 0x07;		/* Enable and reset TX and RX FIFO. */

		//   	NVIC_EnableIRQ(UART1_IRQn);

    LPC_UART1->IER = IER_RBR | IER_THRE | IER_RLS;	/* Enable UART1 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 uart_send( uint32_t portNum, const char *BufferPtr, uint32_t Length )
{
	//unsigned int *U0LSR = (unsigned int *)0x4000C014;	

  if(portNum == 0) {
    while(Length != 0) {
			/* THRE status, contain valid data */
			//while ( !(UART0TxEmpty & 0x01) );
			//			while(((*U0LSR) & 0b100000) != 0);
			while((LPC_UART0->LSR & 0b100000) == 0);

			LPC_UART0->THR = *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) );	
	  LPC_UART1->THR = *BufferPtr;
	  UART1TxEmpty = 0;	/* not empty in the THR until it shifts out */
	  BufferPtr++;
	  Length--;
    }
  }
  return;
}

void uart_receive(uint32_t portNum, char *BufferPtr, uint32_t Length)
{
  if(portNum == 0) {
    while(Length != 0) {
			/* THRE status, contain valid data */
			//while ( !(UART0TxEmpty & 0x01) );
			//			while(((*U0LSR) & 0b100000) != 0);
			while((LPC_UART0->LSR & 0b1) == 0);

			*BufferPtr = LPC_UART0->RBR;
			BufferPtr++;
			Length--;
		}
  } else {
		/*
		while ( Length != 0 )
    {
	  while ( !(UART1TxEmpty & 0x01) );	
	  LPC_UART1->THR = *BufferPtr;
	  UART1TxEmpty = 0;	// not empty in the THR until it shifts out
	  BufferPtr++;
	  Length--;
    }
		*/
  }
  return;
}

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