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 Post subject: VESA Programming
PostPosted: Sun Aug 25, 2002 6:18 am 
Hey again,

I was wondering if anyone knows of some really good protected mode VESA programming tutorials, specifcally information on direct port access or some way to access the hardware directly.

Also, how do I map the Linear Frame Buffer into Physical Memory.

Thanks.


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 Post subject: Re:VESA Programming
PostPosted: Mon Aug 26, 2002 4:15 pm 
There are NO tutorials availible on using VESA. :'( There are docs, but no tutorials. Docs for VESA can be found here:
http://www.vesa.org/

K.J.


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 Post subject: Re:VESA Programming
PostPosted: Mon Aug 26, 2002 5:29 pm 
I guess I could kinda write one right here...
This partial example uses vesa in protected mode to give you a function to call (inplace of int 10h and mov ax, bankswitchcommand) to switch video memory banks:
ax = 0x4f0a
bx = 0
int 0x10 ; in real mode!

;In protected mode (psudo code)
pmBuffer = alloc cx bytes in pmode
make memory (pmBuffer) executable/read-only (if need be)

copy real mode memory (es:di) to new buffer (cx bytes long, as above)

bankRoutine = (pmBuffer + pmBuffer->setWindow);

BankRoutine is a void-void function (takes no paramaters, returns no paramaters) so you set the registers like you would for a bank switch then instead of calling int 10h, you call bankRoutine.
I still havn't gotten this code to work yet though ( I need a malloc function in ASM)

Hope you can figgure out how to use it.


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 Post subject: Re:VESA Programming
PostPosted: Tue Aug 27, 2002 4:23 am 
Ok, check out these tutorials/examples on VBE and protected mode:

1. High-res high-speed VESA tutorial:

"http://www.monstersoft.com/tutorial1/"

2. Protected Mode, High Resolution Graphics Tutorial:

"http://courses.ece.uiuc.edu/ece291/archive/mp/f99/mp5/tutorial.html"

3. VESA coding examples (works in real and/or protected mode):

http://www.monstersoft.com/download/vesa1.zip

Take care. Hope that helps!


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