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void UART0_Init(int BaudRate)
{
unsigned int brd = (Fpclk / BaudRate << 4);
// Connect P0.0 & P0.1 to Tx & Rx
PINSEL0 &= 0xFFFFFFF0; // Reset P0.0 & P0.1
PINSEL0 |= 0x00000001; // Connect P0.0 to Tx
PINSEL0 |= 0x00000004; // Connect P0.1 to Rx
// Set Terminal Characteristics
U0LCR |= 0x02; // 8 Bits Word Select
U0LCR &= 0xFB; // 1 Stop Bit
U0LCR &= 0xF7; // No Parity
U0LCR |= 0x80; // DLAB = 1 to change Baudrate
/*
X-TAL = 12Mhz
Multiple = 5
Divide = 2
--> CPU Clock = X-TAL*Multiple = 60Mhz
Peripheral Clock PCLK = CPU Clk/4 = 15Mhz
*/
// Set Baudrate
U0DLL = (brd & 0xFF);
U0DLM = (brd >> 8);
U0LCR &= 0x7F; // DLAB = 0 to stop change BaudRate
// FIFO Enable
U0FCR |= 0x01; // FIFO Enable
U0FCR |= 0x02; // Rx Reset
U0FCR |= 0x04; // Tx Reset
U0FCR &= 0x3F; // Trigger Level 0
}
. 
/******************************************************************************/
/* RETARGET.C: 'Retarget' layer for target-dependent low level functions */
/******************************************************************************/
/* This file is part of the uVision/ARM development tools. */
/* Copyright (c) 2005 Keil Software. All rights reserved. */
/* This software may only be used under the terms of a valid, current, */
/* end user licence from KEIL for a compatible version of KEIL software */
/* development tools. Nothing else gives you the right to use this software. */
/******************************************************************************/
#include <stdio.h>
#include "serial0.h"
#pragma import(__use_no_semihosting_swi)
//extern long timeval; /* in Time.c */
struct __FILE { int handle; /* Add whatever you need here */ };
FILE __stdout;
FILE __stdin;
int fputc(int ch, FILE *f) {
return (sendchar(ch));
}
int fgetc(FILE *f) {
return (sendchar(getkey()));
}
int ferror(FILE *f) {
/* Your implementation of ferror */
return EOF;
}
void _ttywrch(int ch) {
sendchar (ch);
}
void _sys_exit(int return_code) {
while (1); /* endless loop */
}
#include "LPC214x.H" // LPC2148 MPU Register
#include "serial0.h"
/******************************/
/* Initial UART0 = 9600,N,8,1 */
/* VPB(pclk) = 60.00 MHz */
/******************************/
/******************************/
/* Write Character To UART0 */
/******************************/
int sendchar (int ch)
{
if (ch == '\n')
{
while (!(U0LSR & 0x20)); // Wait TXD Buffer Empty
U0THR = 0x0D; // Write CR
}
while (!(U0LSR & 0x20)); // Wait TXD Buffer Empty
return (U0THR = ch); // Write Character
}
/*****************************/
/* Read Character From UART0 */
/*****************************/
int getkey (void)
{
while (!(U0LSR & 0x01)); // Wait RXD Receive Data Ready
return (U0RBR); // Get Receice Data & Return
}
void init_serial0 (void)
{
PINSEL0 &= 0xFFFFFFF0; // Reset P0.0,P0.1 Pin Config
PINSEL0 |= 0x00000001; // Select P0.0 = TxD(UART0)
PINSEL0 |= 0x00000004; // Select P0.1 = RxD(UART0)
U0LCR &= 0xFC; // Reset Word Select(1:0)
U0LCR |= 0x03; // Data Bit = 8 Bit
U0LCR &= 0xFB; // Stop Bit = 1 Bit
U0LCR &= 0xF7; // Parity = Disable
U0LCR &= 0xBF; // Disable Break Control
U0LCR |= 0x80; // Enable Programming of Divisor Latches
// U0DLM:U0DLL = 15.00 MHz / [16 x Baud]
// = 15.00 MHz / [16 x 9600]
// = 97.6 = 98 = 0062H
U0DLM = 0x00; // Program Divisor Latch(391) for 9600 Baud
U0DLL = 0x62;
U0LCR &= 0x7F; // Disable Programming of Divisor Latches
U0FCR |= 0x01; // FIF0 Enable
U0FCR |= 0x02; // RX FIFO Reset
U0FCR |= 0x04; // TX FIFO Reset
U0FCR &= 0x3F;
}
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