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Diffstat (limited to 'man/3/vid')
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diff --git a/man/3/vid b/man/3/vid new file mode 100644 index 00000000..e21645e6 --- /dev/null +++ b/man/3/vid @@ -0,0 +1,64 @@ +.TH VID 3 MPC823 +.SH NAME +vid \- Motorola 823 video output +.SH SYNOPSIS +.B bind -b #v /dev +.PP +.B /dev/viddata +.br +.B /dev/vidctl +.br +.B /dev/vidcram +.SH DESCRIPTION +The +.I vid +device serves two +files giving basic access +to the on-chip video output of the Motorola 823. +It assumes a video hardware configuration exactly like that of the 823FADS +board, with an I²C interface to an off-chip ADV7176 NTSC/PAL converter +at I²C address 0x54. +.PP +The control device +.B vidctl +accepts the following commands: +.TP +.B on +Disable LCD panel (if present) and enable output from the video frame buffer. +.TP +.B off +Stop display from the video frame buffer and re-enable the LCD panel (if present). +.TP +.BI mode " m" +Set the video output format to +.IR m , +which is one of: +.BR ntsc , +.BR pal-i , +.B pal-m +or +.BR pal-n . +This command is only effective when video output is off. +When next switched on, the both the video controller RAM and +ADV7176 are reprogrammed to the new format. +.PP +Video data can be written to the video frame buffer +by writes of the +.B viddata +file. +The file offset selects the starting byte within the frame buffer. +Reads return the corresponding data from the frame buffer. +The application is responsible for formatting the data as the 823's video +encoder requires, for the selected video format. +.PP +The file +.B vidcram +gives read and write access to the contents of the +video control RAM. +The file offset addresses bytes in the RAM; values can be read from or +written to the RAM in groups of 4-byte big-endian words. +.SH SOURCE +.B /os/mpc/devvid.c +.SH BUGS +Square pixel mode cannot be used on the FADS board: +no suitable video clock source is available. |