Hello,
I have been programming in assembly for the AVR, PIC, and SX microcontrollers for some time and really enjoy it. I have done video, sound, and many DSP projects without any problem, so assembly feels like a second language to me now. Although I have only toyed with MASM (made a few graphics demos), I think it will not be all that hard to get a handle on. I would like to try doing the following project, and was wondering if I may be getting over my head?...
I want to write a basic interpreter/OS much like qbasic/basica that will simply run on any x86 machine by booting from a disk or from HD. I only need the ultimate basics - 640k max, mode13 VGA, and the ability to load and save files. I do not want to use DOS or DR.Dos, I want my program to boot and then enter basic directly. In the end, I will be able to make any x86 computer from a brand new P4 to a 286 run my system with equal results (minus speed of course).
Any feedback, advice would be helpful. I could probably manage the basic interpreter already, since I have done something similar on two microcontrollers already, but to write a bootable x86 program from scratch using no third party code, I am very lost.
Thanks,
Brad
Hi Brad,
Welcome on board. Your task sounds like an interesting one but a rather complex one as you have 2 things to do, a minimum OS and a basic interpreter. Without using the dos and bios interrupts you will have to write the whole lot yourself which is no mean task.
On and off there have been a reasonable number of people who have written their own hobby OS, usually on a floppy disk which for testing purposes means it can be tested using a VM in Windows.