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DLPDLCR230NPEVM: output through projector and HDMI display

Part Number: DLPDLCR230NPEVM

I currently have the DLP evaluation module set up and controlled by a Raspberry Pi 4B, according to the setup guidelines in the manual.

I want the Pi to display its screen simultaneously through the EVM and through a monitor attached to the HDMI port of the Pi. 

From my understanding, it's the python scripts in section 9.3 of the "dlpu103a.pdf" users guide is what controls this, specifically,  init_fpdlink_mode.py and the init_parallel_mode.py, which I'm currently using when activating the EVM on the Pi.  

Are there modifications to those scripts that would still activate output through the EVM projector, but maintain the same output through the HDMI port? My understanding of how the code works is not even close to strong enough to know how to approach this myself. Maybe this also requires modification to the GPIO overlays and config.txt file in section 9.1 of the same user guide? 

For a better understanding of my project, I'm using the EVM for a proof-of-concept prototype, where we will use the Pi to control the DMD mirrors and evaluation module LEDs, like by displaying different colored images with the Pi. However we won't be able to navigate the Pi GUI without a second display, since the evaluation module will be partially disassembled and modified for these tests, and therefore not projecting an image. Hence, that's why simultaneously displaying though and HDMI monitor and the DLP module is important.

  • Hello User,

    Welcome to the E2E forum and thank you for your interest in DLP® technology!

    There is bad news and then good news regarding HDMI monitor use with the DLPDLCR230NPEVM. The bad news is that the config.txt file is needed for the interface between the 230NP EVM and the Raspberry Pi changes the video timings so that they are specifically geared for the EVM, and so the Raspberry Pi will not be able to interface with a monitor directly through an HDMI cable. If you attempt to connect a monitor you will likely see the Raspberry Pi rainbow gradient screen.

    The good news is that there is still a way to view the Raspberry Pi desktop while the Pi is connected to the 230NP EVM. To do so you will need to connect to the Raspberry Pi with a PC over a VNC connection. This is done similarly to the SSH process laid out in the 230NP EVM User's Guide, but in place of using a command line terminal to connect through SSH, you will need to use the same IP address in VNC® Viewer. VNC® Viewer is available to download for free from the Real VNC website. Real VNC has published an article on how to connect to a Raspberry Pi through VNC Viewer, and you can find it here.

    Regards,
    Austin