.TH VID 3 MPC823.SH NAMEvid \- Motorola 823 video output.SH SYNOPSIS.B bind -b #v /dev.PP.B /dev/viddata.br.B /dev/vidctl.br.B /dev/vidcram.SH DESCRIPTIONThe.I viddevice serves twofiles giving basic accessto the on-chip video output of the Motorola 823.It assumes a video hardware configuration exactly like that of the 823FADSboard, with an I²C interface to an off-chip ADV7176 NTSC/PAL converterat I²C address 0x54..PPThe control device.B vidctlaccepts the following commands:.TP.B onDisable LCD panel (if present) and enable output from the video frame buffer..TP.B offStop 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-mor.BR pal-n .This command is only effective when video output is off.When next switched on, the both the video controller RAM andADV7176 are reprogrammed to the new format..PPVideo data can be written to the video frame bufferby writes of the.B viddatafile.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 videoencoder requires, for the selected video format..PPThe file.B vidcramgives read and write access to the contents of thevideo control RAM.The file offset addresses bytes in the RAM; values can be read from orwritten to the RAM in groups of 4-byte big-endian words..SH SOURCE.B /os/mpc/devvid.c.SH BUGSSquare pixel mode cannot be used on the FADS board:no suitable video clock source is available.