Dos Is Still Alive

[popcorn]

dma is only used when you enable it by using smartdrv.or else it will eat your hdd and cpu while copying a huge file.if smartdrv is enabled then it wont use much cpu. it will use ram more.also speed depends more on available base memory which is limited to 640KB only.hence if you load more programs in upper memory then u get increased in speeds in dos.

 

[netfreak]

It depends on BIOS.DOS hands over HDD read and HDD write commands to INT 13h.Some BIOS are pretty bad and have code only for programmed I/O. Others (specially IBM) are better. But yes, if a program desires then the program can engage in DMA itself and smartdrv is one of such programs.

 

[max]

thanks netfreak, will try out

 

[netfreak]

If you want some code to test, here is one

how to screw up your HDD (Erase partition table)

Run command "debug" in dos, eter followinf code/commands

- f 200 L200 0- a 100xxxx:xxxx mov ax,301 (ignore segment :offset values at left)xxxx:xxxx mov bx,200xxxx:xxxx mov cx,1xxxx:xxxx mov dx,0080xxxx:xxxx int 13xxxx:xxxx int 3xxxx:xxxx (Press ENTER an extra time here)- g=100- q

Now run FDISK....

It wont see any partition.

Ofcourse do it only on VM

 

[netfreak]

QUOTE(max @ May 15 2006, 10:45 PM) [snapback]51396[/snapback]
thanks netfreak, will try out
[/b]

Here is an article from Digg.. author of this article tries to modify the BIOS

 

[max]

umm...is the link hidden or something?

 

[netfreak]

http://os-fun.blogspot.com/2006/05/modifyi...or-fun-and.html

Forgot the link

 

[Sushubh]

 

[vishalrao]

I wanted to play the old comedy adventure game "Day Of The Tentacle" but was having problems with FreeDOS so tried DOSbox which worked well: DOSBox, a x86 emulator with DOS