MC9S12XS128 串口操作例程.doc

MC9S12XS128 串口操作例程Code Warrior 4.7Target : MC9S12XS128Crystal: 16.000Mhzbusclock: 8.000MHzpllclock: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 nr,but can get a higher speedstatic 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; /outputCR return; while(!(SCI0SR1&0x80) ; /keep waiting when not empty SCI0DRL=ch;void putstr(char ch) unsigned char ptr=0; while(chptr) uart_putchar(unsigned char)chptr+); static void padding( const int l_flag) int i; if (do_padding & l_flag & (len num1) for (i=len; i 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; n = 0; cp = *linep; while (isdigit(*cp) n = n*10 + (*cp+) - 0); *linep = cp; return(n);void printp( char* ctrl, .) int long_flag; int dot_flag; char ch; va_list argp; va_start( argp, ctrl); for ( ; *ctrl; ctrl+) /* move format string chars to buffer until a format control is found. */ if (*ctrl != %) uart_putchar(*ctrl);#if CR_as_CRLF=TRUE if(*ctrl=n) uart_putchar(r);#endif continue; /* initialize all the flags for this format. */ dot_flag = long_flag = left_flag = do_padding = 0; pad_character = ; num2=32767;try_next: ch = *(+ctrl); if (isdigit(ch) if (dot_flag) num2 = getnum(&ctrl); else if (ch = 0) pad_character = 0; num1 = getnum(&ctrl); do_padding = 1; ctrl-; goto try_next; switch (tolower(ch) case %: uart_putchar( %); continue; case -: left_flag = 1; break; case .: dot_flag = 1; break; case l: long_flag = 1; break; case d: if (long_flag =1 ) if(ch = D) outnum( va_arg(argp, unsigned long), 10L , 0);continue; else /* ch = d */ outnum( va_arg(argp, long), 10L,1);continue; else if(ch = D) outnum( va_arg(argp, unsigned int),10L,0);continue; else /* ch = d */ outnum( va_arg(argp, int), 10L,1); continue; case x: / X 无符号 ， x 有符号 if (long_flag =1 ) if(ch = X) outnum( va_arg(argp, unsigned long), 16L,0); continue; else /* ch = x */ outnum( va_arg(argp, long), 16L,1); continue; else if(ch = X) outnum( va_arg(argp, unsigned int), 16L,0); continue; else /* ch = x */ outnum( va_arg(argp, int), 16L,1); continue; /如果按照16进制打印，将全部按照无符号数进行 continue; case s: outs( va_arg( argp, char*); continue; case c: uart_putchar( va_arg( argp, int); continue; default: continue; goto try_next; va_end( argp); #pragma CODE_SEG _NEAR_SEG NON_BANKEDvoid interrupt 20 SCI0_ISR(void) SCI0CR2_RIE=0; /此处为串口中断需要处理的事情 uart_putchar(uart_getkey(); PORTA_PA0=PORTA_PA0; SCI0CR2_RIE = 1;#pragma CODE_SEG DEFAULT/-void setbusclock(void) CLKSEL=0X00;/disengage PLL to system PLLCTL_PLLON=1;/turn on PLL SYNR=1; REFDV=1; /pllclock=2*osc*(1+SYNR)/(1+REFDV)=32MHz; _asm(nop); /BUS CLOCK=16M _asm(nop); while(!(CRGFLG_LOCK=1); /when pll is steady ,then use it; CLKSEL_PLLSEL =1; /engage PLL to system;/-static void SCI_Init(void) SCI0CR1 =0x00; SCI0CR2 =0x2c; /enable Receive Full Interrupt,RX enable,Tx enable SCI0BD =0x68; /SCI0BDL=busclk/(16*SCI0BDL) /busclk 8MHz, 9600bps,SCI0BD=0x34 /busclk 16MHz, 9600bps,SCI0BD=0x68 /busclk 24MHz, 9600bps,SCI0BD=0x9C /busclk 32MHz, 9600bps,SCI0BD=0xD0 /busclk 40MHz, 9600bps,SCI0BD=0x106/-void Dly_ms(int ms) int ii,jj; if (ms1) ms=1; for(ii=0;iims;ii