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Problems in saving (and parameter passing ) a 32 bit value in the flash.

Amilcar Peres

I took this sentence from the Getting started manual:
".. or if too many arguments are
involved, fixed memory locations are used for those extra arguments."

How do I use this?
I intend to to do the follwing
iap_programming_flash_data_dword(long int value, unsigned int address );
and
iap_programming_flash_data_word(long int value, unsigned int address );

Parents
  • 0 in reply to Drew Davis

    I implemented my self a assbembly code and I call it from a C function.So as I am already using R2 and R3 for the address (r2 and R3 hold the low and high part of DPTR). I think its not neccessary to do what you are suggesting.Am I wrong?

    Here is the assembly code I worte to implemnt:
    ; **********************************************************************
    ; function: iap_program_data_dword SEGUNDA VERSAO
    ; prototype: unsigned char iap_program_data_byte(unsigned char val, unsigned int addr);
    ; description: programs a byte in the flash. passed is the byte and the
    ; 16-bit address. zero is returned for success, non zero is returned for
    ; failiure.
    ; **********************************************************************
    RSEG ?PR?_iap_program_data_dword?IAP
    _iap_program_data_dword:
    PUSH IE ; disable interrupts
    CLR EA
    MOV A,CMOD
    MOV R2,A ; store copy of CMOD
    JNB ACC.6,?IAPTWDOG ; if watchdog enabled then disable
    ANL CMOD,#0BFH
    ?IAPTWDOG:
    ORL AUXR1,#020H ; enable bootrom
    MOV R0,iap_freq ; osc frequency
    MOV R1,#02H

    MOV DPH,R2 ; address to program
    MOV DPL,R3

    MOV A ,R4 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    INC DPTR
    MOV A,R5 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    INC DPTR
    MOV A,R6 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    INC DPTR
    MOV A ,R7 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    ANL AUXR1,#0DFH ; disable bootrom
    MOV CMOD,R2 ; restore CMOD (restore watchdog state)
    POP IE ; restore interrupts to initial state
    RET
    ; end of iap_program_data_dword
    END

    Problem:
    1.The assembler and compiler sends a warning:
    REFERENCE MADE TO UNRESOLVED EXTERNAL
    I dont know why (maybe I am not paying the necessary attention!) but it seems that the compiler does not recognize the existence of such code.

Reply
  • 0 in reply to Drew Davis

    I implemented my self a assbembly code and I call it from a C function.So as I am already using R2 and R3 for the address (r2 and R3 hold the low and high part of DPTR). I think its not neccessary to do what you are suggesting.Am I wrong?

    Here is the assembly code I worte to implemnt:
    ; **********************************************************************
    ; function: iap_program_data_dword SEGUNDA VERSAO
    ; prototype: unsigned char iap_program_data_byte(unsigned char val, unsigned int addr);
    ; description: programs a byte in the flash. passed is the byte and the
    ; 16-bit address. zero is returned for success, non zero is returned for
    ; failiure.
    ; **********************************************************************
    RSEG ?PR?_iap_program_data_dword?IAP
    _iap_program_data_dword:
    PUSH IE ; disable interrupts
    CLR EA
    MOV A,CMOD
    MOV R2,A ; store copy of CMOD
    JNB ACC.6,?IAPTWDOG ; if watchdog enabled then disable
    ANL CMOD,#0BFH
    ?IAPTWDOG:
    ORL AUXR1,#020H ; enable bootrom
    MOV R0,iap_freq ; osc frequency
    MOV R1,#02H

    MOV DPH,R2 ; address to program
    MOV DPL,R3

    MOV A ,R4 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    INC DPTR
    MOV A,R5 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    INC DPTR
    MOV A,R6 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    INC DPTR
    MOV A ,R7 ; data to write
    CALL 0FFF0H ; call iap routine
    MOV R7,A ; id in accumulator

    ANL AUXR1,#0DFH ; disable bootrom
    MOV CMOD,R2 ; restore CMOD (restore watchdog state)
    POP IE ; restore interrupts to initial state
    RET
    ; end of iap_program_data_dword
    END

    Problem:
    1.The assembler and compiler sends a warning:
    REFERENCE MADE TO UNRESOLVED EXTERNAL
    I dont know why (maybe I am not paying the necessary attention!) but it seems that the compiler does not recognize the existence of such code.

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