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DOS开发编程 & 发展交流（开发室） » In-Depth VESA Application Design - Setting 1280x1024x64K@85Hz

Floor1　lcn	Posted 2003-11-12 00:00
初级用户　Posts 4　Credits 112
VESA's 11AH. The default is 1280x1024x64k@60Hz. Does anyone know how to raise the refresh rate to 85Hz or 75Hz? The method I know is based on the VESA 3.0 manual: mode number +800H, then set the corresponding screen characteristics. After I used it, the refresh rate did go up to 85Hz, but the screen graphics got stretched very long. Rewriting specific ports can also work, but my knowledge is limited, and I didn't succeed. I only know that the pixel clock has to be rewritten. Also: using the monitor's GTF can get some CRTC parameters, but I don't know the exact way to use it. I'd like to ask the experts here for guidance.

Floor3　冷石_jasv	Posted 2003-11-18 00:00
初级用户　Posts 27　Credits 182
Man, I've worked myself to death just to manage 1024x768x256, how could I worry about refresh rate too? I even have to write the point-drawing program myself.

Floor4　lcn	Posted 2003-11-25 00:00
初级用户　Posts 4　Credits 112
I've already written the basic functions for points, lines, and so on. The only thing left is this refresh rate. Experts, please help!

Floor5　冷石_jasv	Posted 2003-11-26 00:00
初级用户　Posts 27　Credits 182
http://klwhzh6187681.nease.net/study256/study_a1.htm Go take a look at this website, this is already the peak of graphical interfaces under DOS, written in C It mentions the refresh rate issue I'm using QBasic, and I really don't want to keep writing anymore, it's too tiring

Floor6　lcn	Posted 2003-11-27 00:00
初级用户　Posts 4　Credits 112
Thanks, 冷石_jasv. I'm rather slow-witted; I searched the whole site and still didn't find anything about refresh rate, it only talked about point-drawing speed.