forsyth20121205-174063a80cc13 years agoHistory
247 lines · 4.8 KB · Text
RawDownload
.TH VGA 3.SH NAMEvga \- VGA controller device.SH SYNOPSIS.B bind #v /dev.PP.B /dev/vgactl.br.B /dev/vgaovlctl.br.B /dev/vgaovl.SH DESCRIPTIONThe VGA device allows configuration of a graphics controlleron a PC (and any other platform with VGA devices)..B Vgactlallows control over higher-level settings such as display height, width, depth,controller and hardware-cursor type.Along with the I/O-port registersprovided by.IR arch (3),it is used to implement configuration and setup of VGA controller cards.....This is usually performed by.....IR vga (8)..PPWriting strings to .B vgactlconfigures the VGA device.The following are valid commands..TP.BI size " X" x Y x "Z chan"Set the size of the screen image to be.I X pixels wideand.I Y pixels high.Each pixel is .I Z bits as specified by .IR chan ,whose format is described in.IR image (6)..TP.BI actualsize " X" x YSet the physical size of the display to be.I Xpixels wide by.I Y pixels high.This message is optional;it is used to implement panning and to accommodatedisplays that require the in-memory screen imageto have certain alignment properties.For example, a 1400x1050 screen with a 1408x1050 in-memory imagewill use .B "size 1408x1050but.BR "actualsize 1400x1050" ..TP.BI panning " mode"Depending on whether.I modeis .B onor.BR off ,enable or disable panning in a virtual screen.If panning is on and the screen's.B sizeis larger than its.BR actualsize ,the displayed portion of the screen will pan to follow the mouse.Setting the panning mode after the first attach of the.B #idriver has no effect..TP.BI type " ctlr"Set the type of VGA controller being used..I Ctlris one of .BR ark200pv ,.BR clgd542x ,.BR clgd546x ,.BR ct65545 ,.BR cyber938x ,.BR hiqvideo ,.BR mach64xx ,.BR mga2164w ,.BR neomagic ,.BR s3 ,and.BR t2r4 ..IPNote that this list does not indicate the full set of VGA chipssupported. For example,.B s3includes the 86C801/5, 86C928, Vision864, and Vision964.It is the job of a user-level program....IR vga (8)to recognise which particular chip is being used and to initialize itappropriately..TP.BI hwgc " gc"Set the type of hardware graphics cursor being used..I Gcis one of.BR ark200pvhwgc ,.BR bt485hwgc ,.BR clgd542xhwgc ,.BR clgd546xhwgc ,.BR ct65545hwgc ,.BR cyber938xhwgc ,.BR hiqvideohwgc ,.BR mach64xxhwgc ,.BR mga2164whwgc ,.BR neomagichwgc ,.BR rgb524hwgc ,.BR s3hwgc ,.BR t2r4hwgc ,.BR tvp3020hwgc ,and.BR tvp3026hwgc .A value of.B offdisables the cursor.There is no software cursor..TP.BI palettedepth " d"Set the number of bits of precision used by the VGA palette to .IR d ,which must be either .B 6or.BR 8 ..TP.B blankBlank the screen.This consists of setting the hardwarecolor map to all black as well as, on some controllers, setting theVGA hsync and vsync signals so as to turn offVESA DPMS-compliant monitors.The screen also blanks after 30 minutes of inactivity.The screen can be unblanked by moving the mouse..TP.BI blanktime " minutes"Set the timeout before thescreen blanks; the default is 30 minutes.If.I minutesis zero, blanking is disabled..TP.BI hwaccel " mode"Depending on whether.I modeis .B onor.BR off ,enable or disable whether hardware acceleration(currently for rectangle filling and moving)used by the graphics engine.The default setting is.BR on ..TP.BI hwblank " mode"Depending on whether.I modeis.B onor.BR off ,enable or disable the use of DPMS blanking(see.B blankabove)..TP.BI linear " size align"Use a linear screen aperture of size.I sizealigned on an.IR align -byteboundary..TP.B drawinitInitialize the graphics hardware.This must be sent after setting the.BR type ..PPReading.B vgactlreturns the current settings, one per line..PPSome VGA cards support overlay graphics.Writing strings to.B vgaovlctlconfigures such cards.The following are valid overlay control commands:.TP.BI openctlopens the overlay device..TP.BI configure " w h format"allocates resources inside the driver to support an overlay areaof width.I wand height.I hpixels.  Currently, the only supported.I formatis.B YUYVpacked.In.B YUYVtwo pixels are encoded by their separate Y valuesand their combined U and V values.The size of the two pixels is 32 bits..TP.BI enable " x y w h"enables drawing data on the display through the overlay mode.  The datais drawn at position.IR x , yand has a width and height of.IR w , hrespectively..TP.BI closectlterminates overlay control..PPOverlay data can be written to.BR vgaovl ..SH EXAMPLESThe following disables hardware acceleration..IP.EXecho hwaccel off > /dev/vgactl.EE.SH SOURCE.B /os/pc/devvga.c.SH SEE ALSO.IR arch (3)....IR vga (8).SH BUGSThe hardware graphics cursor on the.B et4000does not work in 2x8-bit mode.