The simplest S3c2440UART function test-EEWORLD

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/**********************************************
* File name: UART.c
* Function: the most basic UART sending and receiving
* Author: No jianqi
* Version: 1.0
************************************************/
#include"2440addr.h" //Includes the settings of 2440 related registers
#include "def.h"
//The four LEDs correspond to GPB5.6.7.8.
#define LED1 5
#define LED2 6
#define LED3 7
#define LED4 8
#define BAUD 115200 //Baud rate
#define Bit(x) (1<
#define Output(x) (1<<2*x) //Set the corresponding IO to output
#define LED_On(x) rGPBDAT=~Bit(x) //Light up the corresponding LED
/**********************************************
* Name: Clk_Set
* Function: Initialization of system clock
* Entry parameters: None
* Export parameters: None
************************************************/
void Clk_Set(void)
{
int count;
rUPLLCON=(56<<12)|(2<<4)|2; //UCLK is 48MHZ
for(count=0;count<10;count++)
{
;
}
rMPLLCON=(92<<12)|(1<<4)|1; //FCLK is 400MHZ
rCLKDIVN=(0<<3)|(2<<1)|1; //HCLK is 100MHZ, PCLK is 50MHZ
rCAMDIVN=(0<<9); //PCLK=HCLK/4
}
/**********************************************
* Name: IO_init
* Function: Initialize the LED port
* Entry parameters: None
* Export parameters: None
************************************************/
void IO_init(void)
{
rGPBCON=Output(LED1)|Output(LED2)|Output(LED3)|Output(LED4); //Set the LED IO port to output
rGPBDAT=0xffff; //All LEDs are off
}
/**********************************************
* Name: UART0_init
* Function: UART0 related initialization work
* Entry parameters: None
* Export parameters: None
************************************************/
void UART0_init(void)
{
rGPHCON=0xa0; //IO port enables UART0 function
rGPHUP=0xff; //Pull-up disabled
rULCON0=0x03; // 8-bit data, no parity, 1 stop bit
rUCON0=0x05; //pclk clock, interrupt request mode is Tx-level, Rx-pulse
rUBRDIV0=26; //Set the baud rate
rUFCON0=0x00; //Do not use FIFO
rUMCON0=0x00; //Do not use flow control
}
/**********************************************
* Name: Send_Byte
* Function: Send a character
* Input parameters: characters waiting to be sent
* Export parameters: None
************************************************/
void Send_Byte(char data)
{
while(!(rUTRSTAT0&0x2)); //Wait for the send buffer to be empty
rUTXH0=data;
}
/**********************************************
* Name: Send_String
* Function: Send string
* Input parameter: string to be sent
* Export parameters: None
************************************************/
void Send_String(char* pt)
{
while(*pt)
{
Send_Byte(*pt++);
}
}
/**********************************************
* Name: Uart_Getch
* Function: Receive a character
* Entry parameters: None
* Export parameter: received characters
************************************************/
char Uart_Getch(void)
{
while(!(rUTRSTAT0&0x1)); //Wait for the receive buffer to have data
return (rURXH0); //Read data
}
/**********************************************
* Name: Main
* Function: Test UART sending and receiving functions
* Entry parameters: None
* Export parameters: None
************************************************/
void Main(void)
{
char temp;
IO_init();
UART0_init();
Clk_Set();
Send_String("HelloWorld"); //Send string
while(1)
{
temp=Uart_Getch(); //Receive characters
if(temp==0x01)
{
LED_On(LED1);
}
}
}

Keywords：S3c2440 UART Reference address：The simplest S3c2440UART function test

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