rom_2.c

Low End Microchip PICs C函数

// copyright, Peter H Anderson, Baltimore, MD, Jan, '02

#case

#device PIC18C452

#fuses XT, NOWDT, NOPROTECT, NOOSCSEN, NOBROWNOUT, PUT, CCP2C1//, STVREN`

#include <defs_18c.h>
#include <delay.h>
#include <ser_18c.h>


#define FALSE 0
#define TRUE !0

struct TABLE
{
	byte ptr_u;
	byte ptr_h;
	byte ptr_l;
	byte lat;
};

void get_str_mem(byte str_num, char *s);
void out_str(char *s);

void TBL_to_RAM(struct TABLE *p);
void RAM_to_TBL(struct TABLE *p);
void decrement_table_ptr(struct TABLE *p);

void main(void)
{
   byte n;
   char s[80];

   ser_init();
   while(1)
   {
       printf(ser_char, "\n\r......................\n\r");
       
       get_str_mem(0, s);
       out_str(s);
       ser_newline();
       
       get_str_mem(1, s);
       out_str(s);
       ser_newline();
       
       get_str_mem(2, s);
       out_str(s);
       ser_newline();       

   }
}

void get_str_mem(byte str_num, char *s)
{

   byte str_counter = 0, n, dat;

   long max_num = 0x1000;

   struct TABLE program_table_save, compiler_table_save;

	program_table_save.ptr_u = 0x00;
	program_table_save.ptr_h = 0x10;
	program_table_save.ptr_l = 0x00;

   decrement_table_ptr(&program_table_save);


	TBL_to_RAM(&compiler_table_save);	// save the compiler values
	RAM_to_TBL(&program_table_save);	// fetch the program values

	while(1)
	{
		if (str_counter == str_num)	// if this is the string
		{

		   n = 0;
	      while(1)							// continually read to s until null
	      {

#asm
            TBLRD
#endasm
            dat = TABLAT;
            s[n] = dat;
            if (s[n] == '\0')
            {
 		         break;
	 		   }
		      ++n;
		      if (n==80)
		      {
		  	        break;
		      }

		   }
		   break;		// done
       } // end of if

       else
       {
			 while(1) 					// go to the next null
			 {
#asm
             TBLRD
#endasm
             dat = TABLAT;
             if (dat == '\0')
             {
					  ++str_counter;
					  break;
				 }
			 }
		} // of else
   } // of outter while(1)

   RAM_to_TBL(&compiler_table_save);	// restore the compiler values
}


void out_str(char *s)
{
	byte n;

	n=0;
	while(s[n])
	{
		ser_char(s[n]);
		++n;
      if (n==80)
      {
         break;
      }
	}
}


void TBL_to_RAM(struct TABLE *p)
{
	p->ptr_u = TBLPTRU;
	p->ptr_h = TBLPTRH;
    p->ptr_l = TBLPTRL;
    p->lat = TABLAT;
}

void RAM_to_TBL(struct TABLE *p)
{
    TBLPTRU = p->ptr_u;
    TBLPTRH = p->ptr_h;
    TBLPTRL = p->ptr_l;
    TABLAT = p->lat;
}

void decrement_table_ptr(struct TABLE *p)
{
	--(p->ptr_l);
	if (p->ptr_l == 0xff)
	{
		--(p->ptr_h);
		if (p->ptr_h == 0xff)
		{
			--(p->ptr_u);
         p->ptr_u = p->ptr_u & 0x0f;
		}
	}
}


#rom 0x1000 = {'M'}
#rom 0x1001 = {'o'}
#rom 0x1002 = {'r'}
#rom 0x1003 = {'g'}
#rom 0x1004 = {'a'}
#rom 0x1005 = {'n'}
#rom 0x1006 = {' '}
#rom 0x1007 = {'S'}
#rom 0x1008 = {'t'}
#rom 0x1009 = {'a'}
#rom 0x100a = {'t'}
#rom 0x100b = {'e'}
#rom 0x100c = {' '}
#rom 0x100d = {'U'}
#rom 0x100e = {'n'}
#rom 0x100f = {'i'}
#rom 0x1010 = {'v'}
#rom 0x1011 = {'e'}
#rom 0x1012 = {'r'}
#rom 0x1013 = {'s'}
#rom 0x1014 = {'i'}
#rom 0x1015 = {'t'}
#rom 0x1016 = {'y'}
#rom 0x1017 = {'\0'}

#rom 0x1018 = {'H'}
#rom 0x1019 = {'e'}
#rom 0x101a = {'l'}
#rom 0x101b = {'l'}
#rom 0x101c = {'o'}
#rom 0x101d = {'\0'}

#rom 0x101e = {'1'}
#rom 0x101f = {'2'}
#rom 0x1020 = {'3'}
#rom 0x1021 = {'4'}
#rom 0x1022 = {'5'}
#rom 0x1023 = {'6'}
#rom 0x1024 = {'7'}
#rom 0x1025 = {'8'}
#rom 0x1026 = {'9'}
#rom 0x1027 = {'\0'}


#include <delay.c>
#include <ser_18c.c>