ssinfod

far to near pointer conversion. (MC9S12DP512)

Discussion created by ssinfod on Oct 18, 2006
Latest reply on Oct 20, 2006 by ssinfod
Hi,
 
I want to display a char[] from a banked page without using the -CpPPAGE=RUNTIME compiler option.
 
I think I can use the lower 2 bytes of the address of the char[] since I will display the data from the same page.
 
So my goal is to convert a char *far  to a char *near.
*far is on 3 bytes : Page, High address, Low address
*near is on 2 byers : High address, Low address.
 
The code below works but I have a compiler warning. What is exact way to convert a *far to a *near without a compiler warning.
 
Note : The data and the code are in page 3D.
 
Thanks..
 
#pragma CONST_SEG __PPAGE_SEG BANKED_DATA_3D                                   
static const char my_string[] = "This is a string";                         // Located in page 3D
 
#pragma CODE_SEG ROM_3D
#pragma CONST_SEG CONST_3D
void far_pstr(const sc *far ptr)
{
   while (*ptr) { putchar(*ptr++); }
}
void near_pstr(const sc *ptr)
{
   while (*ptr) { putchar(*ptr++); }
}
void print_test(void)
{
   char *ptr = my_string;      // This gives  :   Warning : C1860: Pointer conversion: possible loss of data
   char *near ptr2 = (char *near) my_string; // This gives  :   Warning : C1860: Pointer conversion: possible loss of data
  
   near_pstr(my_string);     // This gives  :   Warning : C1860: Pointer conversion: possible loss of data
   far_pstr(my_string);     // This gives  :   Warning : C12002: Use DPAGE, PPAGE, EPAGE to specify the page register. Assumed DPAGE
 
}
 
 

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