#include <cpu_prog_model.h>

void  init_screen(),
      clear_screen();

short display_page();

extern char *dub_screen [];

void home( code)
PM *code;
{
   unsigned short int address;

   if (!dub_screen [0] || !dub_screen [1])
      init_screen();
   else
      clear_screen();

   code->Me [0x25] = code->Me [0x22];
   code->Me [0x24] = 0;

   for (address = 0x0400;address < 0x0800;address ++)
      if (display_page( address) )
         code->Me [address] = 0xA0;
}

void bascalc( vertical, code)
short   vertical;
PM    * code;
{
   short temp_value;

   code->Me [0x29] = ( (vertical >> 1) & 0x3) | 0x4;

   if (vertical & 0x1)
      code->Me [0x28] = temp_value = ((vertical & 0x18) + 0x80) & 0xFF;
   else
      code->Me [0x28] = temp_value = vertical & 0x18;

   code->Ca = (temp_value & 0x40) == 0x40;
   code->Ac = (code->Me [0x28] |= ( (temp_value << 2) & 0xFF) );
}

void wait( code)
PM *code;
{
   /*                                 printf("<Wait.>\n");*/
   code->Ac = 0;
}