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SpyderTL wrote:Any time you see repeated three stacked horizontal lines followed by an S, you are printing your 16-bit Interrupt Table to the screen. This is likely because you are passing a null to a draw string function, so it is drawing everything from RAM address zero until it finds a null value.

Ch4ozz wrote:Your drawstring function probably draws a string but your passing single characters to it which simply wont work.
Either code a proper printf function and you can use

Code: Select all

printf("%c", kbdus[keycode]);

or you find another solution.

SpyderTL wrote:

thehardcoreOS wrote:Should I use SendEOI Inside my kbd and timer handlers?

Yes. You should notify the master PIC any time it signals an IRQ (0-7), and notify both the master and slave PIC when the slave PIC signals an IRQ (8-15). Any IRQs that you have unmasked should have valid interrupt handlers that will notify the proper PICs installed before you unmask them.

thehardcoreOS wrote:When I enable while(1) loop I can use my timer and my keyboard. But I get these weird glyphs:

Any time you see repeated three stacked horizontal lines followed by an S, you are printing your 16-bit Interrupt Table to the screen. This is likely because you are passing a null to a draw string function, so it is drawing everything from RAM address zero until it finds a null value.

That's my guess.

(I get this a lot, by the way.. )

omarrx024 wrote:

SpyderTL wrote:Any time you see repeated three stacked horizontal lines followed by an S, you are printing your 16-bit Interrupt Table to the screen. This is likely because you are passing a null to a draw string function, so it is drawing everything from RAM address zero until it finds a null value.

Which is why we use paging to prevent this.

thehardcoreOS wrote:It is sad that I still don't have any kind of memory management. Paging is my next big thing on the list.
Also I already know that: string paging; paging = "hell".

thehardcoreOS wrote:Hmm, about that slave master EOI sending etc, I already have that function inside my IRQ_Handler that does the same exact thing, to just copy paste it inside my Keyboard_Handler and Timer_Handler?

What do you mean by it prints 16bit interrupt table? I don't think so, because it prints only what I tell it to print. Little bit confused in there. Drawing from RAM??? I don't have any kind of memory management set up and I don't interact with RAM as fair as I know, or maybe I do?

Hmm, about that slave master EOI sending etc, I already have that function inside my IRQ_Handler that does the same exact thing, to just copy paste it inside my Keyboard_Handler and Timer_Handler?

SpyderTL wrote:What I meant to say is that whenever I see that pattern on the screen, with three horizontal lines and an S, it looks like what you would see if you copied the bytes starting at RAM address zero to the screen.

onlyonemac wrote:

SpyderTL wrote:What I meant to say is that whenever I see that pattern on the screen, with three horizontal lines and an S, it looks like what you would see if you copied the bytes starting at RAM address zero to the screen.

Oh, so that's why I always get an S when I pass a NULL pointer to a string output function in my kernel, I never realised that. Not that it's a problem, just fascinating.

SpyderTL wrote:There is a difference between passing a null address and passing an address to an empty string. If I had to guess, I'd say that your code is passing a null address.

thehardcoreOS wrote:

SpyderTL wrote:There is a difference between passing a null address and passing an address to an empty string. If I had to guess, I'd say that your code is passing a null address.

No worries, I fixed it.
For all future generations reading this: don't be stupid like me and instead of PrintStringFunction use PrintCharacterFunction and everything should be just fine.

omarrx024 wrote:

thehardcoreOS wrote:It is sad that I still don't have any kind of memory management. Paging is my next big thing on the list.
Also I already know that: string paging; paging = "hell".

Paging is actually very easy; but beginners to it seem to think it's difficult and I thought so myself.

Ch4ozz wrote:

thehardcoreOS wrote:

SpyderTL wrote:There is a difference between passing a null address and passing an address to an empty string. If I had to guess, I'd say that your code is passing a null address.

No worries, I fixed it.
For all future generations reading this: don't be stupid like me and instead of PrintStringFunction use PrintCharacterFunction and everything should be just fine.

Thats what I told you before didnt I?

SpyderTL wrote:

thehardcoreOS wrote:Hmm, about that slave master EOI sending etc, I already have that function inside my IRQ_Handler that does the same exact thing, to just copy paste it inside my Keyboard_Handler and Timer_Handler?

What do you mean by it prints 16bit interrupt table? I don't think so, because it prints only what I tell it to print. Little bit confused in there. Drawing from RAM??? I don't have any kind of memory management set up and I don't interact with RAM as fair as I know, or maybe I do?

What I meant to say is that whenever I see that pattern on the screen, with three horizontal lines and an S, it looks like what you would see if you copied the bytes starting at RAM address zero to the screen.

RAM address 0000:0000 is where the interrupt handler table is located when the machine first boots. My guess is that you are (accidentally) passing the wrong address to your print string function, and from the looks of the screen, I'm guessing that your print string function is attempting to draw whatever string is sitting at memory address zero.

Maybe that is a hint to help you track down the actual problem, but I could be wrong.

Hmm, about that slave master EOI sending etc, I already have that function inside my IRQ_Handler that does the same exact thing, to just copy paste it inside my Keyboard_Handler and Timer_Handler?

No, you only have to send the EOI once per interrupt (for each PIC, of course). Your original code looks like you were sending it twice per interrupt. I'm assuming that's fixed now.

omarrx024 wrote:

Code: Select all

void ps2_wait_write()
{
	while(inb(0x64) & 2 == 0);
}

void ps2_wait_read()
{
	while(inb(0x64) & 1 == 0);
}

void ps2_wait_write()
{
	while((inb(0x64) & 2) != 0);
}

void ps2_wait_read()
{
	while((inb(0x64) & 1) != 0);
}