The Driver:

# 1 The Driver:

Contents of this section

The Video7 driver has only been tested on a Headland Technologies HT216-32 chip, but should work on other Video 7/Headland Technologies chips as well.

Currently this implementation of the video7 driver only supports single bank mode, which can cause performance degradation, and makes no attempt to distinguish between the different video7 chips.

It also does not probe for memory, so in your `XF86Config` file, make sure that you use the following line:

            Videoram XXX

Where XXX is the amount of RAM in your card. Most of them have at least 512k, so this is a good value to start with.

Also, the clock probing function of XFree86 doesn't seem to correctly get the clocks. The documentation I used (vgadoc3) suggests using the following values for the `Clocks line` in your `XF86Config` file:

            Clocks        25.175 28.322 30.000 32.514 34.000 36.000 38.000 40.000

For 800x600 mode, use a dot clock of 38 instead of 36 or 40 as suggested in most of the sample `XF86Config` files and `modeDB.txt.` This seems to be what is used in the BIOS mode (0x69) which is the 800x600 in 256 colors.

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