80x50 text mode

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woody

Joined: 18 Jun 2005
Posts: 14

woody

Hi all

I was just wondering, how do I set up text mode for 80x50 character output but text mode only. I can manage to set up 1024x768(vbe) which gives roughly the same effect. Is it something to do with loading 8x8 font Question

I was hopeing to have the same situation as with 80x25 writing directly to the graphics memory b8000 (if my memory is correct) but with 80x50 or maybe 80x43.

Any help would be appreciated Razz

Thanks
Woody

19 Jun 2005, 21:47

Chewy509

Joined: 19 Jun 2003
Posts: 297
Location: Bris-vegas, Australia

Chewy509

Just switch to mode 03h, and load the 8x8 font.

Code:

;Set 80x50 text mode...
mov ax, 0003h
int 10h ;first set mode 03h
xor bx, bx
mov ax, 1112h
int 10h ;load 8x8 font (we hope that controller has 
        ; an internal font that we can use).

After that, it works the same way as 80x25, except you now have more lines to play with. (If you would like the code to do it without using the BIOS, let me know and I'll post it up).

19 Jun 2005, 23:50

woody

Joined: 18 Jun 2005
Posts: 14

woody

Hi all.
So just to be clear, I can address this like normal (b800).
Thanks in advance
Woody

P.S.
Could you post the none BIOS code. Thanks.

20 Jun 2005, 00:29

Dex4u

Joined: 08 Feb 2005
Posts: 1601
Location: web

Dex4u

You can use it just like 80x25, but if you are using it in your own OS you need to remember when making your screen functions, that the screen is "50" not "25" for things like scroll, clear screen etc.
My OS called "Dex4u" users that mode for the CLI.
http://falconrybells.co.uk/screenshots.htm
Also note that BOCHs may not display the fonts right, when emulating.

20 Jun 2005, 01:09

Chewy509

Joined: 19 Jun 2003
Posts: 297
Location: Bris-vegas, Australia

Chewy509

woody wrote:

So just to be clear, I can address this like normal (b800).

By all means, YES.

For the non-BIOS version, goto: http://chewy509.atspace.com/index.html and download the LOST source.

The files you are after are:
Lost/SRC/DRIVERS/6845.asm <-- high level functions (write_str, move cursor, etc)
Lost/SRC/DRIVERS/6845_txt.asm <-- contains the mode switch code.
Lost/SRC/DRIVERS/mode03.fon <-- font
Lost/SRC/DRIVERS/mode03.reg <-- Register equates

The source is in NASM, so shouldn't be a problem to port over to FASM.

The code is heavily based on the many mode switch tutorials available on the net, so I won't take credit for it. But AFAIK it is public domain.

20 Jun 2005, 04:00

woody

Joined: 18 Jun 2005
Posts: 14

woody

Hi all.
Thanks for the help Chewy509 the first reply works like a treat. There
seems to be something wrong with your website, when I try to download
the required files I think your host starts to complain with any error message.

Thanks
Woody.

20 Jun 2005, 11:01

smiddy

Joined: 31 Oct 2004
Posts: 557

smiddy

I got he same thing...404 no such file or directory.

20 Jun 2005, 11:27

Chewy509

Joined: 19 Jun 2003
Posts: 297
Location: Bris-vegas, Australia

Chewy509

Fixed, you should be able to get the file now!

20 Jun 2005, 23:16

woody

Joined: 18 Jun 2005
Posts: 14

woody

Thanks....

20 Jun 2005, 23:19

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