Recent Posts

1

Programming with NASM / Re: Using graphical errors

« Last post by Frank Kotler on January 22, 2019, 09:55:10 PM »

Hi Ruud,

"True ascii" characters are 7 bit - that is, 0 to 127. The characters you mention mayt be called "high ascii" (there's really no such thing). They may be part of an ansi standard(?) - which may work on some systems but not all - such as the forum software, You may be stuck with unicode/utf, I can't tell you much about that.

These are the first references I found:

https://en.wikipedia.org/wiki/Box-drawing_character

jrgraphix.net/r/Unicode/2500-257F

You've  probably already seen them. Wish I could help you more!

Best,
Frank

2

Using NASM / Re: can't assemble simple .asm file to .rdf format

« Last post by johntk on January 22, 2019, 09:34:56 PM »

I explained this last year in my other posts.  I am writing my own OS. and I was using rdf but I am using elf now.  It is not that important, I just thought that this was a simple problem to fix but if it is to hard or not worth anyone's time to fix this problem then don't worry about it.  I did put this on Bugzilla last year.  I am doing my OS. development on a windows machine which makes it harder but I have gotten a gcc cross compiler and linker and it works.
John.

3

Programming with NASM / Using graphical errors

« Last post by RuudB on January 22, 2019, 11:30:02 AM »

Hello,

I'm writing my own diagnostic ROM for the IBM-PC/XT and I want to draw a box that represents the on board dip switch block(s). So I used '<causes database error???>'  as top of the blocks of the IBM-PC and my screen went black. Checking the LST I found that Nasm had translated each grahical char to three bytes. The only thing I can guess is that it has to do with UTF. I checked the manual but unfortunately that didn't make me any wiser.

OK, I found a work around by using ' db 191, 191, 196' etc. but I still would like to know if I can use graphical characters as I intended to and, if yes, how.

Thank you very much in advance!

EDIT: even the forum software has problems with these characters. I just hope you understand which characters I mean.

Kind regards, Ruud Baltissen

4

Other Discussion / Re: Recommend me a Linux version

« Last post by christeena on January 22, 2019, 04:48:47 AM »

This article is helpful to know about the steps to installing Linux. Linux is free and open-source software operating systems. It is easy to set up and pop ups chrome the interface similar to Windows. Thanks for sharing these details.   

5

Programming with NASM / Re: Variable

« Last post by debs3759 on January 19, 2019, 07:14:16 PM »

It looks like you are trying to add 1 to var1 then load the result in r9.

What you are actually doing is load r9 with the value stored at the memory location starting at the second byte of var1.

6

Programming with NASM / Re: nasm + lld-link

« Last post by debs3759 on January 19, 2019, 07:10:33 PM »

Import is not a processor directive, it is a macro that generates a series of commands, and it is not part of nasm. If you really need to use it, you will need MASM.

7

Programming with NASM / Variable

« Last post by Siko7 on January 19, 2019, 01:18:04 PM »

Can someone explain, why the value of the register R9 = 0x200000000000000 and not 0x1 is?

Tanks a lot.

Code: [Select]

SECTION .data
var1: dq 0 ; Variable 1 is initialized to 0
SECTION .text
_start:
mov R9, [var1+1]


8

Programming with NASM / Re: nasm + lld-link

« Last post by NASM on January 19, 2019, 05:45:53 AM »

I still do not understand how to import functions?




pexports C:\Windows\System32\user32.dll > user32.def
dlltool -d user32.def -l user32.lib

9

Using NASM / How do I run a posix exe?

« Last post by ben321 on January 16, 2019, 08:40:59 AM »

I compiled a very simple exe file, and used alink to link it. I set the linker to link it as a posix exe file. I assumed when I double clicked on the exe file, it would then cause windows to start the posix (aka linux) subsystem, and then proceed to use that posix subsystem to execute the exe file. But that didn't happen. Instead, it just gave me the error that it couldn't be run from Windows in 32bit mode (what it typically does for 16bit EXE files). This is a 32bit EXE file though. Only difference is it is a linux EXE file, it should be running from within the posix subsystem.

Please help me here. Thanks in advance.

10

Using NASM / How do I generate correct debugging info?

« Last post by ben321 on January 16, 2019, 02:58:03 AM »

I want to debug my program I wrote in NASM by using OllyDbg. Without that, OllyDbg does not label the functions by their correct name, and leaves them as unnamed functions. OllyDbg accepts PDB files (the same file type exported by VB6 when it compiles an EXE), which would store the function names, so as to make debugging easier. Does NASM allow the exporting of Visual Basic format PDB files? By the way, PDB means Program Database, if I remember correctly. I'm not sure if it's only a Microsoft thing, or an industry standard format. It contains info to allow debuggers (such as OllyDbg) to keep the names of functions, so that it's easy to see when a particular function is being referenced in the code.