jgraves@next.com (John Graves) (04/13/91)
I hate to see almost but not quite correct information posted to comp.sys.next.
Regarding the video timing and color monitor specs, here are some numbers:
* The file /usr/include/nextdev/video.h defines the number of visible pixels in a
horizontal line and the size of a horizontal line in VRAM (1120 and 1152, respectively).
Similarly, there are 832 visible vertical lines, but physically 910 fit into VRAM. This
file does not have anything to do with horizontal or vertical sync or blanking times
(front and back porch).
* The horizontal and vertical timing is:
Horizontal Period = Horz Back Porch + Active Video + Horz Front Porch + Horz Sync
16.32 us 2.88 11.20 0.96 1.28
Vertical Period = Vert Back Porch + Active Video + Vert Front Porch + Vertical Sync
14.62 ms 0.783 13.578 0.1306 0.1306
* The pixel clock is 100 MHz.
* The important specs for the color monitor are:
Horz Scan Rate: 61 KHz
Vertical Scan Rate: 68 Hz
NON-INTERLACED
* All of the above information is in the data sheets or can be easily measured with
an oscilloscope.
* Many people don't realize that NeXT also sells a 21" monitor in addition to the
17" monitor which most people have seen. Both monitors use 1120 by 832 pixels and can be
used with NeXTstation Color or NeXTdimension.
Hope this helps,
John