util.c

lpc2138读写SD卡的fat文件系统

// Utility functions
#include <LPC213x.H>                     // LPC21xx definitions
#include <bsp.h>                         // include board support package
#include <stdio.h>

void set_LED(char led_no, char led_cmd) {
  if (led_cmd == ON) {
    if (led_no == ALL) IOSET1 = 0x00FF0000;
	else IOSET1 = (0x00010000 << led_no);
  }
  if (led_cmd == OFF) {
    if (led_no == ALL) IOCLR1 = 0x00FF0000;
    else IOCLR1 = (0x00010000 << led_no);
  }
}

int kp_printf(const char *fmt) {
  if ((U1SCR & 0x04) == 0x04) printf(fmt);
  return(0);
}

char ntoc(unsigned char x)	//given a single digit, return a character for that
{			//digit.			
  switch (x)
  {
  case 9 : return('9');
  case 8 : return('8');
  case 7 : return('7');
  case 6 : return('6');
  case 5 : return('5');
  case 4 : return('4');
  case 3 : return('3');
  case 2 : return('2');
  case 1 : return('1');
  case 0 : return('0');
  }
  return('?');		//return an "F" if if digit is grater than 9
}
 
char htoc(unsigned char x)	//given a single digit, return a character for that
{			//digit.			
  switch (x)
  {
  case 15 : return('F');
  case 14 : return('E');
  case 13 : return('D');
  case 12 : return('C');
  case 11 : return('B');
  case 10 : return('A');
  case 9 : return('9');
  case 8 : return('8');
  case 7 : return('7');
  case 6 : return('6');
  case 5 : return('5');
  case 4 : return('4');
  case 3 : return('3');
  case 2 : return('2');
  case 1 : return('1');
  case 0 : return('0');
  }
  return('?');		//return an "F" if if digit is grater than 9
}

void wr_byte(unsigned char d, unsigned char x)	//d is the number of digits (leading zeros)
{							//routine writes a 3 position digit for the
  char a,b;					//byte value "X".
  a = x/100;				//find the 100's
  if (d == 3) putchar(ntoc(a));	//write out ASCII for the 100's
  b = x - a*100;			//adjust value to the tens
  a = b/10;					//find the number of 10's
  if (d >= 2) putchar(ntoc(a));	//write out the 10's
  a = b - a*10;				//adjust numbers for one's
  putchar(ntoc(a));			//write out the one's
}

void wr_hex(unsigned char x)	//hex number with leading zeros
{							//routine writes a 2 position digit for the
  unsigned int a;			//byte value "X".
  a = x/16;					//find the number of 16's
  putchar(htoc(a));			//write out the 16's
  a = x - a*16;				//adjust numbers for one's
  putchar(htoc(a));			//write out the one's
}

void wr_32hex(unsigned int x)	//hex number for 32 bit value
{
  unsigned int i;		// loop index
  unsigned char a;
  for (i=4;i>0;i--) {	// There is a bug in the compiler... for (i=3;i>=0;i--) doesn't work
    a = x >> (8*(i-1)); // get next byte
	wr_hex(a);			// print ASCII representation of the byte
  }

}
unsigned int read_reg(unsigned int x) {
  return(x);
}