activating digital output of VPBE on dm355evm

This output is activated via u-boot environment varaibles, in particular by 'davinci_enc_mngr.ch0_output=$YourVideoOutputChoiceHere' argument in bootargs; alternatively, it can also bu controlled at runtime via sysfs (see docs in PSP_xx_xx_xx_xx folder within DVSDK for more details)

is there a list of possible bootcommands anywhre?

We list a minimal set of boot commands in our Getting Started Guide; however, for a complete list of u-boot (open source bootloader) options, you can refer to http://www.denx.de/wiki/DULG/Manual

In "SRUEL6" i found 3 Output modes:

COMPOSITE: for analog pal/ntsc output

LCD: for digital output at 640x480 and unknown format

COMPONENT1: for output with THS8200 Encoder

but none of these modes is useful for me.

As I read in http://e2e.ti.com/forums/p/1754/6500.aspx#6500 there is no driver for bt.656 output and I have to create my own, but I dont know how to.

Josef

Josef,

If you go over the VPBE UG (http://focus.ti.com/general/docs/litabsmultiplefilelist.tsp?literatureNumber=spruf72c), you would see that BT.656 digital video output mode is not too difficult to program (the other digital video modes are more complex); the source code for the VPBE Linux drivers are under 

   .../ti-davinci/drivers/video/davinci

I would recommend you study the source code and the VPBE UG, and you should be able to make the necessary changes.