Tag: assembler
-
Hello CP/M z80-world
Actually I don’t know how I ended up exploring CP/M, and that is probably a story in itself. But here I am, summarizing my experiences from getting CP/M up and running on an Altair simulator and writing Hello World in z80 assembly. Getting the environment up and running The simulator altairz80 and cpm2 disk images…
-
Armstrong numbers in x86 assembly
An Armstrong number is a n-digit number that is equal to the sum of each of its digits taken to the nth power. An example using this four digit number 1234:1 ^ 4 + 2 ^ 4 + 3 ^ 4 + 4 ^ 4 = 354, which means it is not an Armstrong number.…
-
Exploring roman numerals in assembly and Python
Turning myself into vacation mode, a small summer coding challenge is always fun and a good way to relax. This time I chose how to convert arabic to roman numerals. It took me a while to figure out the rules regarding which letters can be combined. E.g. I can only be before V or X,…
-
Silly explorations in assembly part 2
I continue to explore assembly language and how to call functions from C. This time we travel back in time to the mid 80s and leave the 64-bit arena that I described here: https://matspetterss.wordpress.com/2023/01/02/silly-explorations-in-assembly-part-1/. OS/2 1.3 – 16-bit I start with OS/2 1.3 that was released somewhere in 1990. It’s a 16-bit operating system, so…
-
Silly explorations in assembly part 1
I actually don’t know what triggered me, but I wanted to better understand the differences in how parameters are passed between functions in different operating systems based on the Intel architecture. At the same time I wanted to keep the scope limited and reuse one C program to be used as driver, and one assembler…
-
Back to the eighties – IBM Xenix 1.0
I’m finished with both my Linux courses and to fill the emptiness from it, I decided to do a short weekend project. Thanks to OS/2 Museum for the inspiration (https://www.os2museum.com/wp/ibm-xenix-two-steps-forward/), which made me look into IBM Xenix 1.0 from the mid 80s. At that time I did not have an 80286 machine, so I never…
-
Doing time traveling with assembly language
I’m taking a distance course at the University in Umeå learning about Linux for development (https://www.umu.se/utbildning/kurser/linux-som-utvecklingsmiljo-1/). The course is covering a lot and it’s been big fun to do the exercises and the teachers are great. Some exercises is about coding in C and some involve debugging. Anyway, firing off the debugger inspired me to…
Mats blog 