How to import identifier from startup.s (to main.c)

Question

I would like to locate a table of constant values with application data (equipment information), preferably at the end of the vector table.

In startup.s I do the following:

    MODULE  ?cstartup

    ;; Forward declaration of sections.
    SECTION CSTACK:DATA:NOROOT(3)

    SECTION .intvec:CODE:NOROOT(2)

    EXTERN  __iar_program_start
    EXTERN  SystemInit        
    PUBLIC  __vector_table

    PUBLIC  _InfoEqData

    DATA
    __vector_table

    DCD     sfe(CSTACK)
    DCD     Reset_Handler             ; Reset Handler

    /* ............... */

    DCD     LCD_IRQHandler                 ; LCD
    DCD     USB_IRQHandler                 ; USB
    __vector_table_end

    _InfoEqData     EQU     __vector_table_end

In main.c I do the following:

#pragma location = _InfoEqData
const EqIdentify_t  eqIdentify = { ... }

When I compile the code shows the following (expected) error

Error[Pe020]: identifier "_InfoEqData" is undefined ... \tst_vBus_main.cpp 25

How do I tell the compiler to find that identifier from startup.s?

Thanks in advance

Answer 1

The IAR toolchain supports #pragma location¹ only to fix data at absolute addresses given by literal numbers² or segment names³.

From my point of view, you should define an own segment in the linker command file³ and locate it according to your requirements.

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¹ IAR C/C++ Compiler User Guide for the 8051Microcontroller Architecture (C8051-7), Seventh edition: March 2017, page 372.

² ibid., Seventh edition: March 2017, page 260.

³ ibid., Seventh edition: March 2017, page 262.

⁴ IAR Linker and Library Tools Reference Guide (XLINK-5001), April 2010, page 21.