NAME
cgthree —
8-bit color frame buffer
SYNOPSIS
cgthree* at sbus?
cgthree* at obio0 (some sun4m models)
wsdisplay* at cgthree?
DESCRIPTION
The cgthree is a color frame buffer,
available as an SBus card or on-board on some sun4c and sun4m workstations.
A small number of frame buffer SBus cards, not manufactured by Sun, are
cgthree-compatible and will also be recognized by the
cgthree driver.
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.
DISPLAY RESOLUTION
Sun frame buffers
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.
Tritec GVC-1, Integrix SFB200
These frame buffers are cgthree-compatible cards with a VGA-compatible video connector. There are only two resolutions supported, selected by jumper JP2 on the card:
| JP2 | Resolution |
open |
1024x768, 60Hz |
short |
1152x900, 66Hz |
SEE ALSO
intro(4), sbus(4), wscons(4), wsdisplay(4)
Sun Frame Buffer FAQ, http://www.sunhelp.org/faq/FrameBuffer.html.