OSDev.org

The Place to Start for Operating System Developers
It is currently Sun Aug 25, 2019 10:41 pm

All times are UTC - 6 hours




Post new topic Reply to topic  [ 6 posts ] 
Author Message
 Post subject: Signup Process
PostPosted: Tue Aug 25, 2009 2:55 pm 
Offline

Joined: Tue Aug 25, 2009 2:49 pm
Posts: 7
Hi,

I've had problems recieving the activation email on my own server. I do not use spam filtering software and have checked the usual things... could anyone check the forum's mail settings and let me know of any reason why I can't use my real email address? The inactive user is called Raptor and I would like to switch to that, with the associated email address, if possible.

Incidentally the answer to the first bot question (what is the source of movsb) is SI in the sign up but Google results seem to say "DS:SI" or even "DS:(E)SI" could someone explain what the differene is?

Thank you


Top
 Profile  
 
 Post subject: Re: Signup Process
PostPosted: Tue Aug 25, 2009 3:24 pm 
Offline
Member
Member
User avatar

Joined: Tue Jun 02, 2009 4:35 pm
Posts: 737
Location: Supporting the cause: Use \tabs to indent code. NOT \x20 spaces.
Hi

SI is one of the Index Registers. SI is a 16 bit register which is native to the 8086, 80186, and 80286, and 80386-SX.

There are two Index Registers: the Source Index (SI) and the (Destination Index) (DI). they are used for string instructions, such as movsb/w, lodsb/w, etc.

The 80386-DX 80486, Pentium, and up, all the way to the last 32 bit Intel processor introduced an expanded set of registers that were, of course, now 32 bit.

The registers that were expanded included SI and DI. (ESI & EDI for 32 bit).

When used in conjunction with a Segment register (any of DS, ES, FS and GS) the index registers are able to point to data symbols/addresses in a different segment. Segmentation is out of the scope of this quick rundown, so you may check the wiki for more info.

Referencing SI, or DI, or their 32 bit counterparts, ESI and EDI, without an appended segement register implies that you are taking data from the current value of the Segment registers.

As a side comment: I don't think it's too wise to admit that you had to google to find the answers to the entry quiz: that defeats the point. :P Welcome and whatnot, and enjoy your stay.

_________________
17:56 < sortie> Paging is called paging because you need to draw it on pages in your notebook to succeed at it.


Top
 Profile  
 
 Post subject: Re: Signup Process
PostPosted: Tue Aug 25, 2009 4:11 pm 
Offline

Joined: Tue Aug 25, 2009 2:49 pm
Posts: 7
Thanks gravaera, I do admit googling for the answer - Learning these things is the reason I wanted to join the forum afterall. I will be learning much more before starting to make anything in assembly though.


Top
 Profile  
 
 Post subject: Re: Signup Process
PostPosted: Tue Aug 25, 2009 4:40 pm 
Offline
Member
Member
User avatar

Joined: Sat Nov 29, 2008 1:07 pm
Posts: 550
Location: Throw a dart at central Texas
gravaera wrote:
As a side comment: I don't think it's too wise to admit that you had to google to find the answers to the entry quiz: that defeats the point. :P Welcome and whatnot, and enjoy your stay.


At least he was smart enough to actually use Google, unlike many n00bs.

_________________
Owner of Fawkes Software.
Wierd Al wrote:
You think your Commodore 64 is really neato,
What kind of chip you got in there, a Dorito?


Top
 Profile  
 
 Post subject: Re: Signup Process
PostPosted: Tue Aug 25, 2009 7:14 pm 
Offline
Member
Member
User avatar

Joined: Sun Feb 18, 2007 7:28 pm
Posts: 1435
Theres an entry quiz now? When did that happen?

_________________
OS Development Series | Project Neptune
char c[2]={"\x90\xC3"};int main(){void(*f)()=(void(__cdecl*)(void))(void*)&c;f();}


Top
 Profile  
 
 Post subject: Re: Signup Process
PostPosted: Wed Aug 26, 2009 1:46 am 
Offline
Member
Member
User avatar

Joined: Sun Oct 22, 2006 7:01 am
Posts: 2631
Location: Devon, UK
Hi,

It's been there for a few months ago and the whole point is that if someone doesn't know the answer, they are able to google for it. It was introduced because of (a) bots and (b) people who didnt bother using Google before asking questions! Welcome, Ratty :)

Cheers,
Adam


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC - 6 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group