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/*****************************************************************************
* uart.c: UART API file for NXP LPC13xx Family Microprocessors
*
* Copyright(C) 2008, NXP Semiconductor
* All rights reserved.
*
* History
* 2008.08.21 ver 1.00 Preliminary version, first Release
*
******************************************************************************/
#include "LPC13xx.h"
#include "uart.h"
// CodeRed - change for CMSIS 1.3
#define SystemFrequency SystemCoreClock
volatile uint32_t UARTStatus;
volatile uint8_t UARTTxEmpty = 1;
volatile uint8_t UARTBuffer[BUFSIZE];
volatile uint32_t UARTCount = 0;
/*****************************************************************************
** Function name: UART_IRQHandler
**
** Descriptions: UART interrupt handler
**
** parameters: None
** Returned value: None
**
*****************************************************************************/
void UART_IRQHandler(void)
{
uint8_t IIRValue, LSRValue;
uint8_t Dummy = Dummy;
IIRValue = LPC_UART->IIR;
IIRValue >>= 1; /* skip pending bit in IIR */
IIRValue &= 0x07; /* check bit 1~3, interrupt identification */
if (IIRValue == IIR_RLS) /* Receive Line Status */
{
LSRValue = LPC_UART->LSR;
/* 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 */
UARTStatus = LSRValue;
Dummy = LPC_UART->RBR; /* Dummy read on RX to clear
interrupt, then bail out */
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 */
UARTBuffer[UARTCount++] = LPC_UART->RBR;
if (UARTCount == BUFSIZE)
{
UARTCount = 0; /* buffer overflow */
}
}
}
else if (IIRValue == IIR_RDA) /* Receive Data Available */
{
/* Receive Data Available */
UARTBuffer[UARTCount++] = LPC_UART->RBR;
if (UARTCount == BUFSIZE)
{
UARTCount = 0; /* buffer overflow */
}
}
else if (IIRValue == IIR_CTI) /* Character timeout indicator */
{
/* Character Time-out indicator */
UARTStatus |= 0x100; /* Bit 9 as the CTI error */
}
else if (IIRValue == IIR_THRE) /* THRE, transmit holding register empty */
{
/* THRE interrupt */
LSRValue = LPC_UART->LSR; /* Check status in the LSR to see if
valid data in U0THR or not */
if (LSRValue & LSR_THRE)
{
UARTTxEmpty = 1;
}
else
{
UARTTxEmpty = 0;
}
}
return;
}
/*****************************************************************************
** Function name: UARTInit
**
** Descriptions: Initialize UART0 port, setup pin select,
** clock, parity, stop bits, FIFO, etc.
**
** parameters: UART baudrate
** Returned value: None
**
*****************************************************************************/
void UARTInit(uint32_t baudrate)
{
uint32_t Fdiv;
uint32_t regVal;
UARTTxEmpty = 1;
UARTCount = 0;
NVIC_DisableIRQ(UART_IRQn);
LPC_IOCON->PIO1_6 &= ~0x07; /* UART I/O config */
LPC_IOCON->PIO1_6 |= 0x01; /* UART RXD */
LPC_IOCON->PIO1_7 &= ~0x07;
LPC_IOCON->PIO1_7 |= 0x01; /* UART TXD */
/* Enable UART clock */
LPC_SYSCON->SYSAHBCLKCTRL |= (1<<12);
LPC_SYSCON->UARTCLKDIV = 0x1; /* divided by 1 */
LPC_UART->LCR = 0x83; /* 8 bits, no Parity, 1 Stop bit */
regVal = LPC_SYSCON->UARTCLKDIV;
Fdiv = (((SystemFrequency/LPC_SYSCON->SYSAHBCLKDIV)/regVal)/16)/baudrate ; /*baud rate */
LPC_UART->DLM = Fdiv / 256;
LPC_UART->DLL = Fdiv % 256;
LPC_UART->LCR = 0x03; /* DLAB = 0 */
LPC_UART->FCR = 0x07; /* Enable and reset TX and RX FIFO. */
/* Read to clear the line status. */
regVal = LPC_UART->LSR;
/* Ensure a clean start, no data in either TX or RX FIFO. */
// CodeRed - added parentheses around comparison in operand of &
while (( LPC_UART->LSR & (LSR_THRE|LSR_TEMT)) != (LSR_THRE|LSR_TEMT) );
while ( LPC_UART->LSR & LSR_RDR )
{
regVal = LPC_UART->RBR; /* Dump data from RX FIFO */
}
/* Enable the UART Interrupt */
NVIC_EnableIRQ(UART_IRQn);
#if TX_INTERRUPT
LPC_UART->IER = IER_RBR | IER_THRE | IER_RLS; /* Enable UART interrupt */
#else
LPC_UART->IER = IER_RBR | IER_RLS; /* Enable UART interrupt */
#endif
return;
}
/*****************************************************************************
** Function name: UARTSend
**
** Descriptions: Send a block of data to the UART 0 port based
** on the data length
**
** parameters: buffer pointer, and data length
** Returned value: None
**
*****************************************************************************/
void UARTSend(uint8_t *BufferPtr, uint32_t Length)
{
while ( Length != 0 )
{
/* THRE status, contain valid data */
#if !TX_INTERRUPT
while ( !(LPC_UART->LSR & LSR_THRE) );
LPC_UART->THR = *BufferPtr;
#else
/* Below flag is set inside the interrupt handler when THRE occurs. */
while ( !(UARTTxEmpty & 0x01) );
LPC_UART->THR = *BufferPtr;
UARTTxEmpty = 0; /* not empty in the THR until it shifts out */
#endif
BufferPtr++;
Length--;
}
return;
}
/******************************************************************************
** End Of File
******************************************************************************/
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