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External RAM memory tester program

John Brown

Hello,
I am trying to check if addresses bus and data bus are well configured in my external RAM memory.
I have done this algorithm

#include <XC164.h>

#define         low_adress   0x400000;
#define         high_adress   0x410000;
#define         high_data   0xFF;
#define         low_data   0x00;

void    main    (void)
{
        static double    idata  j,i,k;
        int xhuge       *DIR;

        DIR  = 0x400000;

        /*      DATA BUS TEST   */

        for (j = low_adress; j <= high_adress; j++)
        {
                *DIR = 0x55;                                    // I write 0101 0101
                if (*DIR != 0x55)       P3^3 = 1;       // If what I have read is diferent to what I have written, I switch on an alarm
                *DIR = 0xAA;                                    // I write 1010 1010
                if (*DIR != 0xAA)       P3^3 = 1;       // If what I have read is diferent to what I have written, I switch on an alarm
                DIR++;
        }

        /*      ADRESSES BUS TEST       */

        DIR  = 0x400000;
        for (i = low_adress; i < high_adress; i = i + 0xFF;)
        {
                for     (k = low_data; k < high_data ; k++)
                {
                        *DIR = k;
                        DIR++;
                }
        }


but the compiler throws errors. My RAM memory is mapped from 0x400000 to 0x410000 (64kB).
Why does the compiler throw this errors?

Build target 'Target 1'
assembling START_V2.A66...
compiling PruebaRA.c...
PRUEBARA.C(17): error C25: syntax error near '='
PRUEBARA.C(17): error C25: syntax error near ';'
PRUEBARA.C(17): error C25: syntax error near ')'
PRUEBARA.C(20): error C25: syntax error near 'if'
PRUEBARA.C(20): error C25: syntax error near 'P3'
PRUEBARA.C(20): error C25: syntax error near '='
PRUEBARA.C(22): error C25: syntax error near 'if'
PRUEBARA.C(22): error C25: syntax error near 'P3'
PRUEBARA.C(22): error C25: syntax error near '='
PRUEBARA.C(24): error C25: syntax error near '}'
PRUEBARA.C(29): error C25: syntax error near 'for'
PRUEBARA.C(29): error C7: compilation aborted
Target not created

Parents
  • 0 in reply to John Brown 

    ASC0_TBUF = memTestDataBus(pointer);


    Will send the result without the use of a variable.

    The datasheet (and possibly your external connections) should tell you where the memory is and how large it is - if your project doesn't know where the memory is, the compiler + linker will not be able to produce a project that makes use of the memory as expected.

    But I want you to once more think about one important issue: If you let the memtest function test a memory cell that is used for stack or for storing any of your variables, you will not get the expected result. The function call may not even return.

Reply
  • 0 in reply to John Brown 

    ASC0_TBUF = memTestDataBus(pointer);


    Will send the result without the use of a variable.

    The datasheet (and possibly your external connections) should tell you where the memory is and how large it is - if your project doesn't know where the memory is, the compiler + linker will not be able to produce a project that makes use of the memory as expected.

    But I want you to once more think about one important issue: If you let the memtest function test a memory cell that is used for stack or for storing any of your variables, you will not get the expected result. The function call may not even return.

Children