The Place to Start for Operating System Developers
https://f.osdev.org/
Code: Select all
macro PRINT String{
local .Printer
local .Nextchar
local .Done
local .a
.Printer:
mov si, .a
mov ah, 0Eh
jmp .Nextchar
.Nextchar:
lodsb
or al, al
jz .Done
int 10h
jmp .Nextchar
jmp .Done
.a db String,10,13,0
.Done:
}
macro SCREEN mode
{
push ax
if mode = 0
mov ah,0h ;SCREEN 0; Default DOS screen mode
mov al,3h
int 10h
else if mode = 13
mov ah,0h ;SCREEN 13; VGA
mov al,13h
int 10h
end if
pop ax
}
macro SLEEP
{
;Output:
;ah = BIOS scancode of key pressed
;al = ASCII character of key pressed
;Could have also used...
; mov ah,8h
; int 21h
mov ah,0h
int 16h
}
macro END
{
mov ax,4Ch ;\END
int 21h ;/
}
macro LOCATE row,col
{
pusha
mov ah,2 ;Function 2
mov bh,0 ;Use page 0
mov dh,row ;row
mov dl,col ;col
int 10h
popa
}
Code: Select all
SCREEN 0
LOCATE 5,5
PRINT "Hello World"
SLEEP
END
.Or simply adhere to the proper standards instead of using special compiler extensions. C++ might be a bit harder because the implementation is so complex, but there should be a simple common subset of features supported by most compilers. And just because something compiles on one arch with a compiler doesn't mean it will work on any other arch with the same compiler. I test my OS on a couple different compilers (mostly gcc and tcc) to make sure everything is proper.gravaera wrote:One solution to portability is to require that no matter what architecture it is to ported to, the compiler should be a cross version of ONE fixed compiler.
In my kernel, as it is so far, it's fully portable (even onto a another (probably embedded) architecture) as long as it's compiled with G++ compiler for that architecture/platform. I DO have a compiler.h setup, but it's really not that flexible. And it's irritating to use. So I end up not really using anything from that compiler.h setup, and therefore end up just having to require that anyone trying to port will have to use a G++ compiler of some sort.
Yes there will always be the need to do some rewriting, but this is not always a bad thing, to mod the underlining design to take addvantage of the processor .NickJohnson wrote:Dex's BASIC-like method would also require rewriting everything... if you want actual portability you might as well use C/C++ (assuming you want portability... that's not always the goal, and an assembly OS has speed and coolness points).
What is KISS?Dex wrote: Yes there will always be the need to do some rewriting, but this is not always a bad thing, to mod the underlining design to take addvantage of the processor .
The basic like method is more usefull for writing the apps in, but if you keep your kernel design KISS, its much easier to port, eg: my OS is abased on KISS and can run on both x86 and arm.
background = 88976EhDex wrote:@Tommy, I like the clock in your demo, would it be possable to post the colors used for the background, digets and shadow, of the clock, as you got the look just right, thinks.
OK.Dex wrote: Here tells what KISS is about http://en.wikipedia.org/wiki/KISS_principle
We (team DexOS) use it, as "Keep It Small and Simple"
This is a weird bug which does not occur in other emulators.Craze Frog wrote:With 32 mb of memory the OS will not boot because it needs "a minimum of 32 mb of memory".
Rewriting has not been beneficial for the OS. Bugs have been fixed, others have emerged. I think it would be wise to takeNickJohnson wrote:Some people start at the GUI and work down, while others start with threading and IPC and work up. If you had both, I would be seriously impressed.
Emulators (and real machines) rarely have/report the amount of memory you think you gave them. A 32MB stick of RAM could only be 31MB, or even less. Emulators also sometimes shave off a few KB/MB, for no real reason (afaik...). It would be wise to set the memory requirement to a small amount less than a power of 2, not just a power of two. It's not as bad as hard drives thoughCraze Frog wrote:With 32 mb of memory the OS will not boot because it needs "a minimum of 32 mb of memory". It has that, so it shouldn't complain.
.It is precisely the problem!NickJohnson wrote:Emulators also sometimes shave off a few KB/MB, for no real reason (afaik...).Craze Frog wrote:With 32 mb of memory the OS will not boot because it needs "a minimum of 32 mb of memory". It has that, so it shouldn't complain.
!
oh well, it looks cool.