cgthree —
8-bit color frame buffer
cgthree* at sbus?
wsdisplay* at cgthree?
The
cgthree is an SBus color frame buffer.
The
cgthree driver interfaces the frame
buffer with the
wscons(4)
console framework. It does not provide direct device driver entry points but
makes its functions available via the internal
wsdisplay(4) interface.
If the
cgthree frame buffer is used as the
console display, it is possible, for some models, to select a different
resolution than the default 1152x900 or 1024x768 by changing the OpenPROM
environment. To change the default resolution, type the following:
ok setenv
output-device screen:r1152x900x66
to change to a 66Hz 1152x900 resolution.
If the
cgthree frame buffer is a secondary
display, or a serial console is used, the display resolution cannot be changed
without using an
nvramrc OpenPROM script. Refer
to the
Sun Frame Buffer FAQ for details.
The
cgthree frame buffer accepts the
following resolutions:
- screen:r1024x768x77
- Super VGA 1024x768, with a refresh rate of 77Hz. This is the default
setting on model 501-2691.
- screen:r1152x900x66
- Standard 1152x900, with a refresh rate of 66Hz. This is the default
setting on older models (501-1415 and 501-8044).
- screen:r1152x900x76
- Standard 1152x900, with a refresh rate of 76Hz. This is the default
setting on more recent models (501-1718 and 501-1909).
Note that not all models support settings other than their default setting.
intro(4),
sbus(4),
wscons(4),
wsdisplay(4)
Sun Frame Buffer FAQ,
http://www.sunhelp.org/faq/FrameBuffer.html.
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