ASSEMBLY - Definition and allocation of segments - problem

[Leojunin]

Hello to all forum. First of all I apologize for my English.

I am programming in assembly

I have a problem using a memory segment. Below is my configuration:

In the .prm file...

SEGMENTS /* Here all RAM/ROM areas of the device are listed. Used in PLACEMENT below. */

    Z_RAM                    =  READ_WRITE   0x0080 TO 0x00EF;

    Z_RAM2                  =  READ_WRITE   0x00F0 TO 0x00FF;

    RAM                      =  READ_WRITE   0x0100 TO 0x06FF;

    RAM2                    =  READ_WRITE   0x0700 TO 0x083F;

    STACK                  =  READ_WRITE   0x0840 TO 0x087F;

    ROM                      =  READ_ONLY    0x8000 TO 0xFFAD;

/* INTVECTS                 =  READ_ONLY    0xFFC0 TO 0xFFFF; Reserved for Interrupt Vectors */

END

PLACEMENT /* Here all predefined and user segments are placed into the SEGMENTS defined above. */

    _DATA_ZEROPAGE,                     /* zero page variables */

    MY_ZEROPAGE                         INTO  Z_RAM;

    Z_PAGE                                     INTO  Z_RAM2;

    DEFAULT_RAM                         INTO  RAM;

    HIGHPAGE                                 INTO  RAM2;

    SSTACK                              INTO  STACK;

    _PRESTART,                          /* startup code */

    STARTUP,                            /* startup data structures */

    ROM_VAR,                            /* constant variables */

    STRINGS,                            /* string literals */

    VIRTUAL_TABLE_SEGMENT,              /* C++ virtual table segment */

    DEFAULT_ROM,

    COPY                                /* copy down information: how to initialize variables */

                                        INTO  ROM;

END

Then in my code, I add ...

; import symbols

           XREF __SEG_END_SSTACK, __SEG_END_DEFAULT_RAM

When compiling, I take the following values:

           LDHX #__SEG_END_SSTACK takes LDHX #0x0880 (correct)

           TXS

           ...

and

           LDX #__SEG_END_DEFAULT_RAM takes LDHX #0x0000 instead of #0x0700

What should I do?

Tanks to all

[trytohelp · Accepted solution]

Hi,

I've performed some tests on my side with CW for MCU v6.3 and CW for MCU V10.6.4.

For both development tools, the linker generates a warning:

    No information available for segment 'DEFAULT_RAM'

Following the tests I did, it seems linker-defined objet is not working for DEFAULT_RAM.

I will create a SR to track the problem.

Keep you informed.

Have a great day,
Pascal
Freescale Technical Support
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[Leojunin]

Tank you, Pascal

I commented that the program is working putting my desired value instead of __SEG_END_DEFAULT_RAM but had forgotten this and when I did a memory restructuring, missed the entire program and could not remember why!

I commented that, although I have the CodeWarrior 10.6 which came with the BDM, I have not installed it, and I'm using version 6.3

[trytohelp]

Hi Daniel,

In all case the problem is on linker side.

I've logged the issue in our bug base under the number ENGR00366601.

To track it I've created a SR# too (1-4058277390).

I don't know when I will receive feedback or information regarding this problem.

I will keep you informed.

Have a great day,
Pascal
Freescale Technical Support
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[Leojunin]

Hello Pascal. The RAM segment I have placed in MY_HIGH_RAM

(MY_HIGH_RAM INTO RAM;) but also assigned the value 0x0000.

I can see the service request to see how it goes and thus, contribute ideas? Where can I find it?

Tank you

[trytohelp]

Hi,

In fact the tool is working as expected.

By default the macro is defined if the segment is used only.

On my examples the DEFAULT_RAM (which is .data too) was not used.

This is why the DEFAULT_RAM was not defined.

If a variable is placed in the DEFAULT_RAM section then the DEFAULT_RAM macro will be defined.

Example of map file:

*********************************************************************************************

OBJECT-ALLOCATION SECTION

    Name              Module                Addr  hSize  dSize    Ref    Section  RLIB

---------------------------------------------------------------------------------------------

MODULE:                -- asm_main_asm.obj --

- PROCEDURES:

    asm_main                                  2132      1A      26      1  MyCode  

- VARIABLES:

    temp_byte                                  80      1      1      1  MY_ZEROPAGE

- LABELS:

    __SEG_END_SSTACK                          302      0      0      2          

    __SEG_END_DEFAULT_ROM                    2132      0      0      1          

    __SEG_END_DEFAULT_RAM                      102      0      0      1          

    __SEG_END___DOT__data                      102      0      0      1          

MODULE:                -- main_c.obj --

- PROCEDURES:

    main                                      211E      14      20      1  .text  

- VARIABLES:

    my_val                                    100      2      2      1  .data  

    i                                          302      2      2      2  .bss    

The my_val is defined as global variable:

    int my_val=10;

This places my_val to DEFAULT_RAM section.

Attached you will find the project.

Have a great day,
Pascal
Freescale Technical Support
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[Leojunin]

Thanks Pascal. I found the description of what you explained to me in the help. Nevertheless I tell you that no data in this segment because they are dynamically allocated by the application. What I did to take that value was, instead of taking the last value of the segment in question (__SEG_END_DEFAULT_RAM), take the value of the next segment, which itself is in use (__SEG_START_SYS_RAM).

[trytohelp]

Yes but this is how it should work according to the manual.

Extract of page 101

+++++++++++++++++++

Listing 3.47 .prm File

LINK example.abs

NAMES example.o END

SECTIONS

MY_RAM = READ_WRITE 0x0800 TO 0x0FFF;

MY_ROM = READ_ONLY 0x8000 TO 0xEFFF;

MY_STACK = NO_INIT 0x400 TO 0x4ff;

END

PLACEMENT

DEFAULT_ROM INTO MY_ROM;

DEFAULT_RAM INTO MY_RAM;

SSTACK INTO MY_STACK;

END

INIT main

Listing 3.48 Linker-Defined Symbols

__SEG_START_SSTACK 0x400

__SEG_END_SSTACK 0x500

__SEG_SIZE_SSTACK 0x100

+++++++++++++++++++

Have a great day,
Pascal
Freescale Technical Support
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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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