For 3D sources on the parallel or MIPI DSI interface, images must be frame sequential (L, R, L, ...) when input to the DLPC34xx controller. Any processing required to unpack 3D images and to convert them to frame sequential input must be done by external electronics prior to inputting the images to the controller. Each 3D source frame input must contain a single eye frame of data, separated by a VSYNC, where an eye frame contains image data for a single left or right eye. The signal 3DR input to the controller indicates whether the input frame is for the left eye or right eye.
Each DMD frame is displayed at the same rate as the input interface frame rate. Figure 11 shows the typical timing for a 50-Hz or 60-Hz 3D HDMI source frame, the input interface of the DLPC34xx controller, and the DMD. In general, video frames sent over the HDMI interface pack both the left and right content into the same video frame. GPIO_04 is optionally sent to a transmitter on the system PCB for wirelessly transmitting a synchronization signal to 3D glasses (usually an IR sync signal). The glasses are then in phase with the DMD images displayed. Alternately, 3D Glasses Operation shows how DLP link pulses can be used instead.