Strange letter displays before string [ACTUALLY SOLVED]

iansjack · **Posted:** Wed Jan 11, 2017 2:55 am

If you think you have fixed the bug, try doing a WriteChar() to position 0, 0.

DixiumOS · **Joined:** Tue Jan 10, 2017 3:19 pm **Posts:** 84

iansjack wrote:

If you think you have fixed the bug, try doing a WriteChar() to position 0, 0.

Woooorks. I already said i changed the math for it to become correct.

Code used:

Code:

   terminal_clrscr();
   terminal_writestring("[", WHITE, BLACK, 0, 0);
   terminal_writestring("Dixium OS", WHITE, LIGHT_BLUE, 1, 0);
   terminal_writestring("]", WHITE, BLACK, 10, 0);
   terminal_writestring("  Write string succesful.", WHITE, BLACK, 11, 0);

Octocontrabass · **Joined:** Mon Mar 25, 2013 7:01 pm **Posts:** 5137

Did you read iansjack's post? He said writechar(), not writestring().

DixiumOS · **Joined:** Tue Jan 10, 2017 3:19 pm **Posts:** 84

Octocontrabass wrote:

Did you read iansjack's post? He said writechar(), not writestring().

Oh, okay, i'll try that.

EDIT: It doesn't work.

matt11235 · **Posted:** Wed Jan 11, 2017 3:43 am

DixiumOS wrote:

Octocontrabass wrote:

This bug.

That isn't a bug

DixiumOS wrote:

EDIT: It doesn't work.

Read through it again, or check the values with a debugger to see the value that you're actually passinig to terminal_writechar.

Anyway, didn't we go through all of this already in your old project?

DixiumOS · **Joined:** Tue Jan 10, 2017 3:19 pm **Posts:** 84

zenzizenzicube wrote:

DixiumOS wrote:

Octocontrabass wrote:

This bug.

That isn't a bug

DixiumOS wrote:

EDIT: It doesn't work.

Read through it again, or check the values with a debugger to see the value that you're actually passinig to terminal_writechar.

Anyway, didn't we go through all of this already in your old project?

" 10007d: 66 89 94 1b fe 7f 0b mov %dx,0xb7ffe(%ebx,%ebx,1)"

The hell are you doing with 0xB7FFE, GCC?
B8000 - 1 does not equal B7FFE.
Let's see if this changes if i change B8000 to B8001.

Nahh...

EDIT: Finally got it working. Ya' little..

Code:

void terminal_writechar(unsigned char c, unsigned char fc, unsigned char bc, int x, int y)
{
   if (x == 80) {
      x = 0;
      y++;
   }
   if (x == 0) {
      x++;
   }
   uint16_t attribute = (bc << 4) | (fc & 0x0F);
   volatile uint16_t * loc;
   loc = (volatile uint16_t *)0xB8000 + (y * 80 + x - 1);
   *loc = c | (attribute << 8);
}

Oh, wait, now terminal_writestring doesn't work. #-o

EDIT: It does, just that i tried writing to line 25. It's 24, not 25.

MDenham · **Joined:** Sat Nov 10, 2012 1:16 pm **Posts:** 62

DixiumOS wrote:

The hell are you doing with 0xB7FFE, GCC?
B8000 - 1 does not equal B7FFE.

Pointer math. If the type you're using for the pointer is short*, "-1" means it subtracts sizeof(short) from the pointer value (and likewise with any other pointer - for t*, -1 subtracts sizeof(t)).

Octocontrabass · **Joined:** Mon Mar 25, 2013 7:01 pm **Posts:** 5137

DixiumOS wrote:

EDIT: Finally got it working. Ya' little..

No, you just added more bugs.

Use terminal_writechar() to put a character at 0,0 and at 1,1. They won't show up at the correct locations.

DixiumOS · **Joined:** Tue Jan 10, 2017 3:19 pm **Posts:** 84

Octocontrabass wrote:

DixiumOS wrote:

EDIT: Finally got it working. Ya' little..

No, you just added more bugs.

Use terminal_writechar() to put a character at 0,0 and at 1,1. They won't show up at the correct locations.

1,1 displays in 0,1, but 0,0 does display in 0,0. I just...

Format is x,y by the way.

EDIT: Just add a x++ and everything will be fine

Code used:

Code:

   terminal_clrscr();
   terminal_writechar_freestanding('a', WHITE, BLUE, 0, 0);
   terminal_writechar_freestanding('b', BLUE, WHITE, 1, 1);
   terminal_writestring_freestanding("I like potato!", BLUE, WHITE, 12, 12);

EDIT: Except terminal_writestring(_freestanding) loves to put it one line down. EDIT TO THAT: Why did i forget again computers count from 0? It should be line 3 if lines were 1-25.

EDIT: After doing some testing, it seems the tty.c forgot something that incremented the value yet again by one. Now i need to remove 2 for it to work.

matt11235 · **Posted:** Wed Jan 11, 2017 5:21 am

DixiumOS wrote:

EDIT: After doing some testing, it seems the tty.c forgot something that incremented the value yet again by one. Now i need to remove 2 for it to work.

Code:

for (size_t i = 0; i < len; i++) {
   x++;
   terminal_writechar(data[i], fc, bc, x, y);
}

Or you could just increment x after calling terminal_writechar, instead of before :roll:

DixiumOS · **Joined:** Tue Jan 10, 2017 3:19 pm **Posts:** 84

And now i just tested. It should say exactly what my real machine just put there:
http://i.imgur.com/wcPmWCf.jpg

andrewthompson555 · **Joined:** Thu Oct 13, 2016 2:07 pm **Posts:** 27

Now I know who NunoLava1998 is... You're him! DixiumOS, you're NunoLava1998. Your GitHub page has NunoLava1998. Everyone calls me it all the time.

Love4Boobies · **Posted:** Wed Jan 11, 2017 6:36 am

Yeah, we know who he is. But somehow you managed to occupy the same space in our minds. That's not his fault.

dozniak · **Posted:** Wed Jan 11, 2017 7:52 am

Hello again, NunoLava1998. I need to update my ignore list again. Please refrain from updating your nickname in the future. Thank you very much!

andrewthompson555 · **Joined:** Thu Oct 13, 2016 2:07 pm **Posts:** 27

Forums are nuts these days... Are you this guy? Are you that guy?! Everything you've done is all wrong. Ugh... Ugh... Ugh! :evil:

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Strange letter displays before string [ACTUALLY SOLVED]

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