OSDev.org

Posted: **Fri Aug 24, 2007 4:53 am**

HI,
About calling AX = 4F02h for setting VBE mode,
but when I set BX D11 bit for setting specified CRTC value
something is wrong, AX return 014F (call function fail)
What is the cause of this error? CRTC value or something else?

look for help, thanks a lot

best regards

Posted: **Wed Aug 29, 2007 9:21 am**

Hi,

Is the CRTC block is stored somewhere that is accessible in real-mode? Otherwise, I guess it must just be unsupported timings - tricky to say without more information.

Cheers,
Adam

Posted: **Wed Aug 29, 2007 7:34 pm**

AJ wrote:Hi,

Is the CRTC block is stored somewhere that is accessible in real-mode? Otherwise, I guess it must just be unsupported timings - tricky to say without more information.

Cheers,
Adam

Smiling...

However, VBE3.0 specifies the CRTC block for setting timings. I reviewed VBE3.0 standard and came to a conclusion. I didn't pass pixel clock to AX = 4F0Bh function to return closest pixel clock. But I don't know how to access 32 bits register in DOS and Turbo C. ECX shall be set to reguest pixel clock. Perhaps you can solve my issue. ho ho...

BR.
Shihwei

OSDev.org

Set CRTC Block and Enable D11 but call funciton fail

Set CRTC Block and Enable D11 but call funciton fail