Direct access to VGA memory

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Dave Allamby

Direct access to VGA memory

Post by Dave Allamby » Fri Nov 09, 2007 5:45 pm

We are looking at upgrading our app to run on QNX6, but want to continue
doing direct access to VGA memory, and depend on console signal to
indicate switch away from current console, to stop/start/refresh
display. Has QNX started supporting the console switch signal (or maybe
frame buffers).

Armin

Re: Direct access to VGA memory

Post by Armin » Sat Nov 10, 2007 11:17 am

Dave Allamby wrote:
We are looking at upgrading our app to run on QNX6, but want to continue
doing direct access to VGA memory, and depend on console signal to
indicate switch away from current console, to stop/start/refresh
display. Has QNX started supporting the console switch signal (or maybe
frame buffers).
Please have a look to http://www.libsdl.org

--Armin

http://www.the-better-idea.com/DviewSDL.htm

Dave Allamby

Re: Direct access to VGA memory

Post by Dave Allamby » Sun Nov 11, 2007 4:27 am

Thanks Armin, will take a look

Dave

Armin wrote:
Dave Allamby wrote:

We are looking at upgrading our app to run on QNX6, but want to
continue doing direct access to VGA memory, and depend on console
signal to indicate switch away from current console, to
stop/start/refresh display. Has QNX started supporting the console
switch signal (or maybe frame buffers).


Please have a look to http://www.libsdl.org

--Armin

http://www.the-better-idea.com/DviewSDL.htm

Mike Gorchak

Re: Direct access to VGA memory

Post by Mike Gorchak » Thu Nov 22, 2007 9:39 am

Hello, Dave!

DA> We are looking at upgrading our app to run on QNX6, but want to
DA> continue doing direct access to VGA memory, and depend on console
DA> signal to indicate switch away from current console, to
DA> stop/start/refresh display. Has QNX started supporting the console
DA> switch signal (or maybe frame buffers).

Just do mmap of physical memory, depends on what memory you need. Use the
following displacements: 0x000B8000 - text mode, 0x000A0000 - VGA graphics
memory, or use mmap device memory library call to do memory mapping of the
BAR0 of your PCI/AGP/PCIE graphics card to obtain access to the full video
adapter framebuffer memory. Or if you are using photon use Pg* photon calls
to obtain pointers to the fragments of the physical graphics card memory.

With best regards, Mike Gorchak. E-mail: mike@malva.ua

John Nagle

Re: Direct access to VGA memory

Post by John Nagle » Fri Feb 29, 2008 10:21 pm

Dave Allamby wrote:
We are looking at upgrading our app to run on QNX6, but want to continue
doing direct access to VGA memory, and depend on console signal to
indicate switch away from current console, to stop/start/refresh
display. Has QNX started supporting the console switch signal (or maybe
frame buffers).
1988 called. It wants mode 13h back.

John Nagle

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