I asked your question before about multiple displays.
Only one output will be active at a time, either the HDMI or composite RCA connector.
I\'m not aware of a LCD video channel at this time on the R-Pi card.
Will you be using the GPIO for the LCD video control channel or the RCA into another device, say a DVD player?
I\'ve not yet looked at the HDMI device spec., I will guess that a HDMI monitor is \"smart\" and can talk to the R-Pi video control logic, where as the RCA is only a hose streaming out of video signals. So if a HDMI is attached to the R-Pi and powered up, the R-Pi will talk to the smarter of the two video channels first. Of course, it sounds like the \"boot\" script can override the sensed signals within the SoC. So under Application Control, you can force the use of either channel, not both at the same time. I would guess that the SoC logic has a Mux to select the video creation for a channel.
I\'m going with the Buy Another R-Pi Card, as an answer to doing multiple monitors. Now I just have to work out the software to sync the video display\'s content. My Application is for an educational station, where multiple displays are actively assisting the student/learner. A proven system, currently costing over $100,000.00 USD. Will be interesting.