Search found 92 matches
- Sun Feb 27, 2011 12:08 pm
- Forum: Beginning OS Development
- Topic: How to read input from user into a double-type variable
- Replies: 3
- Views: 12016
Re: How to read input from user into a double-type variable
The easiest way to get what you want would be to search online for an implementation of strtod (string to double) it's somewhere in the C library. I've heard the Microsoft C library source code is supplied with each Visual C++ compiler, so you could take a look at it. As long as it's written in plai...
- Thu Feb 24, 2011 8:33 pm
- Forum: General Programming
- Topic: Kernel trouble
- Replies: 19
- Views: 104874
Re: Kernel trouble
<EDIT> I've moved the HAL init to the very first thing after the kernel entry sets up the segment registers. Now, instead of crashing due to exceptions being thrown that aren't handled because the IDT and Exception handlers weren't in place, Bochs just hangs. It clears my screen to blue, like it sho...
- Wed Feb 23, 2011 9:26 pm
- Forum: General Programming
- Topic: Kernel trouble
- Replies: 19
- Views: 104874
Re: Kernel trouble
Because your post mentioned that these issues just started occurring lately, I assume that your bootloader has worked fine in the past? Yes, it did. Were there any modifications to the bootloader software? Please do note that the bootloader provided by the series was not designed for kernels that e...
- Tue Feb 22, 2011 8:49 pm
- Forum: General Programming
- Topic: Kernel trouble
- Replies: 19
- Views: 104874
Re: Kernel trouble
...so from here you need to debug your IDT and find out why its double faulting in the first place. Now there's a problem, the IDT isn't set up until the kernel registers its interrupt handlers, which it can't get to because of the errors taking the system down. As it crashes when the 2nd stage jum...
- Fri Feb 18, 2011 1:52 pm
- Forum: Beginners
- Topic: confusion on multiple initialization of GDT
- Replies: 3
- Views: 36295
Re: confusion on multiple initialization of GDT
The GDT in the bootloader was a generic one to make sure we could properly go to protected mode, but it lacked specifics, I.E. privileges and protection, which is fixed by the one created in the kernel. and from this i have got that we can set up new gdt and invalidate the old whenever required? is ...
- Fri Feb 11, 2011 12:25 am
- Forum: Beginning OS Development
- Topic: Bitwise Operations in Physical Memory Manager
- Replies: 5
- Views: 15267
Re: Bitwise Operations in Physical Memory Manager
Am I right in saying that array indexes/values are still linear in memory it is just the values that are read right to left? map[0] map[1] 0000 0000 0000 0000 0000 0000 0000 0000 ... 0000 0000 0000 0000 0000 0010 0000 0000 The bit set as 1 there is the 42nd bit in the memory map that represents the...
- Thu Feb 10, 2011 1:03 pm
- Forum: Beginning OS Development
- Topic: Bitwise Operations in Physical Memory Manager
- Replies: 5
- Views: 15267
Re: Bitwise Operations in Physical Memory Manager
Bits are read from right to left like this:
which would make the set bit bit 23
Code: Select all
bit 31 bit 0
0000 0000 1000 0000 0000 0000 0000 0000
- Wed Feb 09, 2011 8:50 pm
- Forum: General Programming
- Topic: Kernel trouble
- Replies: 19
- Views: 104874
Kernel trouble
Lately, I've been having trouble with triple-faulting when the bootloader jumps to my kernel. Since real hardware doesn't give any info on its registers, I installed Bochs and ran my kernel again. These are the results: Booting from 0000:7c00 interrupt(): gate descriptor is not valid sys seg (vector...
- Sat Feb 05, 2011 9:23 pm
- Forum: General Programming
- Topic: OS Development Series code question
- Replies: 34
- Views: 160180
Re: OS Development Series code question
In response to a previous post of mine: Also, I noticed the kernel is loaded at RealMode address 0x3000, and the stack at 0x9000. Now, a bit of calculating tells me there's roughly 24 KB between those two points in memory. You told me the stack grows downwards... which means that, with my kernel bei...
Re: NASM
It seems like NASM cannot find the file to compile. Are you sure the file Boot1.asm exists?
Otherwise, if your file is boot1.asm, just change the first letter into a capital B, and it should find it, provided the file is located in the same directory as NASM.
Otherwise, if your file is boot1.asm, just change the first letter into a capital B, and it should find it, provided the file is located in the same directory as NASM.
- Tue Jan 11, 2011 4:39 pm
- Forum: News Discussion
- Topic: PE Chapter released
- Replies: 5
- Views: 65897
Re: PE Chapter released
Happy new year to you too, and thx for the update.
- Sat Jan 08, 2011 2:18 pm
- Forum: Assembly Language
- Topic: doubt on int 10(0e) & reading sector
- Replies: 4
- Views: 39916
Re: doubt on int 10(0e) & reading sector
hello guys i have few doubts from int 10 and reading sector from usb i)int 10h int 10 AH = 0E AL = ASCII character to write BH = page number (text modes) BL = foreground pixel color (graphics modes) As you can see what is page number(in BH register) and what do they exactly mean by graphics mode(BL...
- Wed Jan 05, 2011 7:27 pm
- Forum: Beginners
- Topic: simple question
- Replies: 3
- Views: 36748
Re: simple question
You can, but you'll have to make drastic changes to the bootloader to get the bootsector to work. (must be 2048 bytes, last two bytes must be the boot signature 'AA55' etc.) And, of course, you'll need some software to actually write your bootloader to the bootsector of a virtual disc image. I did t...
- Thu Dec 30, 2010 3:58 pm
- Forum: Advanced OS Development
- Topic: Virtual Memory problems in VMWare player
- Replies: 4
- Views: 36954
Re: Virtual Memory problems in VMWare player
Thanks. I'll try that. And sometimes under some optimization levels, kernel memory corruptions occur. I can't understand why those things happen. And VM mapping in Mikes tute is not clear Identity map 1st 4mb Map 3gb to 1mb This way, two pages map to same physical addr. Isn't this a problem? No, it...
- Thu Dec 30, 2010 2:07 pm
- Forum: Advanced OS Development
- Topic: Virtual Memory problems in VMWare player
- Replies: 4
- Views: 36954
Re: Virtual Memory problems in VMWare player
I have a similar problem as you do. Initializing the Virtual Memory Manager triple faults real and virtual hardware. I think I'm gonna revert my VMM to before I started to integrate the User Mode stuff, because that's when it started to fail. Another thing I found odd, was after a couple of changes ...