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Altera_Forum's avatar
Altera_Forum
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15 years ago

assembly language in the nios ii ide

Hi

does the nios ii ide support assemble language?

why does my assemble codes occur errors?

my setup project proceed as follows:

1 Start the Nios II IDE. (Start->All Programs->Altera->NiosII EDS 9-> NiosII

9 IDE

2 Creat a new project. File->New->Project Nios II C/C++ Application

3 Select blankproject from templates

4 Set the project name

5 Select the target hardware( sopc builder system has been setup)

6 Click Next

7 Click New system libary

8 Click Finish

9 Add a file with name basics.s (File->New->Other

This opens a popup where you can pick File from under the General

Category, after selecting File, you need to specify the name at the bottom

(use basics.s)

10 enter the code:

.include"nios_macros.s"

.text

.equ TEST_NUM,0x90abcdef

.global _start

_start:

movia r7,TEST_NUM

mov r4,r7

STRING_COUNTER:

mov r2,r0

STRING_COUNTER_LOOP:

beq r4,r0,END_STRING_COUNTER

srli r5,r4,1

and r4,r4,r5

addi r2,r2,1

br STRING_COUNTER_LOOP

END_STRING_COUNTER:

mov r16,r2

END:

br END

.end

11 Use Debug As -> Nios II Instruction Set Simulator which will build the

project (assemble the file) and start the debugger.

then errors occur

errors： /cygdrive/d/altera/90/nios2eds/components/altera_hal/HAL/src/alt_main.c undefined reference to `main'

/cygdrive/d/altera/90/quartus/FPGA_code/computer_organization/lab_ex1/part1_1/software/asm_first_syslib/Debug/crt0.o(.text+0x0):/cygdrive/d/altera/90/ip/altera/nios2_ip/altera_nios2/HAL/src/crt0.S first defined here

/cygdrive/d/altera/90/quartus/FPGA_code/computer_organization/lab_ex1/part1_1/software/asm_first_syslib/Debug/libasm_first_syslib.a(alt_main.o) In function `alt_main':

Can't open nios_macros.s for reading: No such file or directory

obj/part2.o In function `_start':

Warning: end of file not at end of a line; newline inserted

ps:

1 i'm sure the codes are right(de2-70 labs exercises/computer organization/lab1)

2 the operator proceed is from duke.edu by google

forgive my ugly English,:D.

Best regards

hanshaohua

14 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Use:

    .global _alt_main

    _alt_main:

    instead of:

    .global _start

    _start:

    you need the C runtime startup to initialize the NIOS II system and it jumps to _alt_main.

    Bill
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    you need the C runtime startup to initialize the NIOS II system and it jumps to _alt_main.

    --- Quote End ---

    Strictly speaking, this isn't true. If you drop the Altera provided syslib/bsp entirely, you can avoid all the default C runtime and initialization stuff.

    If you include the syslib/bsp as it appears the OP has done, then you do need to define either _alt_main or _main as you have suggested.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Thank you，Bill.

    I'm new to nios ii system.

    By now, i don't know the assembly code or my wrong operating proceed cause

    wrong.

    But from the nios ide errors tips, nios ii can't recognize the assembly code .
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    Strictly speaking, this isn't true. If you drop the Altera provided syslib/bsp entirely, you can avoid all the default C runtime and initialization stuff.

    If you include the syslib/bsp as it appears the OP has done, then you do need to define either _alt_main or _main as you have suggested.

    --- Quote End ---

    Hi，Kevin.

    It's kind of you .

    I have modifed the assembly code using

    .global _alt_main

    _alt_main:

    instead of

    .global _start

    _start:

    But it does not work, yet occur errors as mentioned by me.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    Have you tried _main instead of _alt_main?

    --- Quote End ---

    yes，have the same errors.

    If there is something wrong with the code, i can continue to work on labs exercises.

    But，if nios ii does not support assembly code , i have no idea how to go on.

    May be i can try nios ii command shell( i'm familiar with linux and know of many commands）.

    :)

    Thanks all the same.

    hanshaohua
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Sorry to ask this but why use assembly language? Why not use C? The NIOS II GCC compiler generates code as good as and probably better than any assembly code I've written.

    Bill
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    Sorry to ask this but why use assembly language? Why not use C? The NIOS II GCC compiler generates code as good as and probably better than any assembly code I've written.

    Bill

    --- Quote End ---

    Hi,bill.

    yes,i am more familiar with C more than assembly language.

    Acutually speaking, i am doing labs exercises using DE2 .

    And DE2 provides assembly codes exercises.

    Most of all, i am new to niso ii system.

    hanshaohua
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Finally, the problem is solved.

    1 assembly file is xx.S,not xx.s

    2 You must have a function or label called main. If main is written in assembly-language, the label main must be declared global with the .global directive.

    3 Project default in Eclipse woring dir would be best.

    Thank you ,Bill,Kevin.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Hi!

    I still have the error, my asm sour file is main.S, the code from a NIOSII tutorial:

    .include "nios_macros.s"

    .equ switches, 0x41020

    .equ leds, 0x41030

    .global main

    main:

    movia r2, switches

    movia r3, leds

    loop:

    ldbio r4, 0(r2)

    stbio r4, 0(r3)

    br loop

    but: alt_main.c:154: undefined reference to `main'

    :(