MC9S12XS128 串口操作例程

MC9S12XS128 串口操作例程

Code Warrior 4.7

Target : MC9S12XS128

Crystal: 16.000Mhz

busclock: 8.000MHz

pllclock:16.000MHz

本程序主要包括以下功能：

1.设置锁相环和总线频率；

2.IO口使用；

3.共四路ATD使用及显示方法。

LED计数，根据灯亮可以读取系统循环了多少次

************************************************************** ***************************/

#include /* common defines and macros */

#include /* derivative information */

#include

#include

#include

#pragma LINK_INFO DERIVATIVE "mc9s12xs128"

#pragma CODE_SEG DEFAULT

#define CR_as_CRLF TRUE // if true , you can use "\n" to act as CR/LF,

// if false, you have to use "\n\r",but can get a higher speed

static int do_padding;

static int left_flag;

static int len;

static int num1;

static int num2;

static char pad_character;

unsigned char uart_getkey(void)

{

while(!(SCI0SR1&0x80)) ; //keep waiting when not empty

return SCI0DRL;

}

/*

void uart_init(void) {

SCI0CR2=0x0c;

SCI0BDH=0x00;//16MHz,19200bps,SCI0BDL=0x1a

SCI0BDL=0x34;//16MHz,9600bps,SCI0BDL=0x34

}

*/

void uart_putchar(unsigned char ch)

{

if (ch == '\n')

{

while(!(SCI0SR1&0x80)) ;

SCI0DRL= 0x0d; //output'CR'

return;

}

while(!(SCI0SR1&0x80)) ; //keep waiting when not empty SCI0DRL=ch;

}

void putstr(char ch[])

{

unsigned char ptr=0;

while(ch[ptr]){

uart_putchar((unsigned char)ch[ptr++]);

}

}

static void padding( const int l_flag)

{

int i;

if (do_padding && l_flag && (len < num1))

for (i=len; i

uart_putchar( pad_character);

}

static void outs( char* lp)

{

/* pad on left if needed */

len = strlen( lp);

padding( !left_flag);

/* Move string to the buffer */

while (*lp && num2--) uart_putchar( *lp++);

/* Pad on right if needed */

len = strlen( lp);

padding( left_flag);

}

static void reoutnum(unsigned long num, unsigned int negative, const long base )

{

char* cp;

char outbuf[32];

const char digits[] = "0123456789ABCDEF";

/* Build number (backwards) in outbuf */

cp = outbuf;

do {

*cp++ = digits[(int)(num % base)];

} while ((num /= base) > 0);

if (negative) *cp++ = '-';

*cp-- = 0;

/* Move the converted number to the buffer and */

/* add in the padding where needed. */

len = strlen(outbuf);

padding( !left_flag);

while (cp >= outbuf)

uart_putchar( *cp--);

padding( left_flag);

}

static void outnum(long num, const long base ,unsigned char sign)//1, signed 0 unsigned

{

unsigned int negative;

if ( (num < 0L) && sign )

{

negative=1;

num = -num;

}

else negative=0;

reoutnum(num,negative,base);

}

static int getnum( char** linep)

{

int n;

char* cp;