561 questions
2
votes
1
answer
117
views
Stuck on Second Stage Bootloader – Turbo C + TASM + DOSBox + QEMU Setup
I'm working on a retro programming project and running into trouble with my bootloader setup. I'm using:
Turbo Assembler 4.01 for the first-stage bootloader (x86 Assembly)
Turbo C 2.0 for the second-...
- 31
1
vote
1
answer
43
views
Where can I assemble my assembly file aside from TASM that supports .STACK
I am just following the book from my university to run this simple code I found as an example for my coding practice. I am new to assembly language.
The problem is that I only know how to assemble in ...
- 11
-1
votes
2
answers
131
views
Switch text mode to video mode in assembly
I have a project I am doing in assembly. I am making a kahoot style quiz game in x86 assembly, running it in DOSBox.
I made the entire thing with no graphics but I need to make it with graphics so I ...
1
vote
0
answers
171
views
387 FPU instructions to load to stack not doing anything?
So I'm coding some stuff in assembly (TASM) for DOS with DOSBox (long story short: for our assembly course assignments the professor says we need to use an environment from the 90s for some reason, ...
- 31
1
vote
1
answer
60
views
Assembler step-mode interrupt handler
I am writing a step-mode interrupt handler in x86 architecture assembler and can't figure out how to find and print out mov byte ptr [bx] and bx registers.
So far i have this and in theory it should ...
- 13
0
votes
0
answers
100
views
How to set/force EXE stack size with 1988 Turbo C 2.0 for a reverse engineering project
i try to reconstruct a Turbo C 2.0 DOS small-memory-model executable C source exact-as-possible from disassembly (its an DOS reverse-engineering project and im using IDA Pro disassembling and UASM for ...
- 777
0
votes
0
answers
64
views
The DOS program seemingly ignores the 'print *' instruction?
This simple program (16-bit assembly using debug on FreeDOS, code below) expects a one-digit integer. It stops if the integer is either 0 or >1. If it's 1, it generates a new line, prints '*', then ...
- 319
1
vote
1
answer
66
views
Resident Program structure and logic
Using 8086 microprocesor and DOSBox.
This resident program is done with those 2 commands:
TASM.exe program.asm &
TLINK.exe /t program.obj
Why is it not working when I run another .exe which has to ...
- 23
1
vote
1
answer
75
views
Multiple counts of "Invalid combination of opcode and operands" error
I have written an assembly program that sorts an array using bubble sort. I am getting errors.
This is the full code:
org 100h
section .data
array db 5, 3, 7, 1, 4, 9, 2, 8, 6
array_size db 9
...
- 11
2
votes
1
answer
51
views
Procedure for printing numbers doesn't work
I'm working with TASM (in DosBOX emulator).
I'm a beginner and I don't know much yet.
Below is my full code. The problem is that it prints out not just expected output (25 + 10 = 35 and 25 - 10 = 15) ...
- 173
-4
votes
1
answer
76
views
Swap 2 lines in text file using assembler
this is my code for swapping 2 lines in DosBox assembly. I can not find out why is it printing the same thing from input.txt to out.txt. I think the problem is with line numbers (and user input). ...
- 3
0
votes
1
answer
56
views
Swap 2 lines in text file with assembler
could someone provide an example how to swap 2 lines in txt document using assembly? I would be using it as an example, because right now i'm able to copy contents from one txt file to another, but ...
- 3
0
votes
1
answer
73
views
Replace digit with a word and write to a file using assembler 8086 [closed]
I'm writing a program that converts digits into words and also writes every other character unchanged to output file. But for some reason the output buffer overwrites characters on top of each other.
...
- 13
1
vote
1
answer
66
views
Timer implementation in NASM assembly on DOSBox
OP's text:
How could I make a backward timer 3 minutes in NASM assembly?
The timer is not working backwards.
Edit:
It looks like split mode works correctly. Not sure about lap mode.
To make a ...
- 11
1
vote
0
answers
50
views
How to print a symbol for a user-provided number of times in DOS assembly x86? [duplicate]
I am a newbie here trying to learn assembly, so I apologise for any trivial mistakes.
The following code is supposed to print '*' n times, where n is a user-provided one-digit decimal integer. However,...
- 319
