Build a Pi Zero W pocket projector! // Project

#66

Has anyone looked at using a DSI bridge (like the Toshiba TC358762 used in the official Raspberry PI DSI display) or an FPGA to connect over the DSI port on full-size Raspberry Pi boards? Lattice have an FPGA line (CrossLink) designed to be used as a display bus interface, including free (but not open source) IP for a DSI to DPI bridge. I don’t have the skills to try it myself, but maybe someone else does.

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#67

Has anyone been successful with this DLP2000 and RPI 4B using the wire method? I am getting just DLP splash screen. I am using 10cm jumpers, enabled I2C, edited all proper files, etc. Could this be related to the on board dual display?

I would be happy to do some testing if anyone has any ideas.

#68

There’re some device tree overlay changes required for DPI to work on the Raspberry Pi 4. https://www.raspberrypi.org/forums/viewtopic.php?f=107&t=244266#p1501249

The problem with the dpi24 overlays is that it hangs its pinmux changes to the framebuffer “fb” node. Pi 4 relies on the vc4-fkms-v3d overlay being applied which disables the old framebuffer and any associated pinmux settings.

A fix for this is for the dpi24 overlay to hedge its bets and attach to both the “fb” node and the “vc4” node, one of which should be enabled. You can download an updated overlay to try from here: https://drive.google.com/file/d/14vR6iq … sp=sharing

Install the update with:

 sudo cp dpi24.dtbo /boot/overlays

Then remove the “gpio=” workaround (if you added it) and reboot. All being well, and provided “dtparam=audio=off” and “enable_uart=off”, your display should work.

– [PhilE] Raspberry Pi Engineer & Forum Moderator

#69

Does this:
“Then remove the “gpio=” workaround (if you added it) and reboot.”
Mean that I need to remove all of the previously amendments to config.txt?
In other words I remove all of this:

Added to support DLP2000

dtoverlay=i2c-gpio,i2c_gpio_sda=23,i2c_gpio_scl=24,i2c_gpio_delay_us=2

dtoverlay=dpi18
overscan_left=0
overscan_right=0
overscan_top=0
overscan_bottom=0
framebuffer_width=854
framebuffer_height=480
enable_dpi_lcd=1
display_default_lcd=1
dpi_group=2
dpi_mode=87

dpi_output_format=458773
hdmi_timings=854 0 14 4 12 480 0 2 3 9 0 0 0 60 0 32000000 3

Thanks in advance

#70

The “gpio=” workaround refers to a workaround the Raspberry Pi forum thread’s OP tried, “gpio=0-27=a2,np” (sets GPIO pins 0 through 27 to alt mode 2 (DPI) and disables pull-up/down. You still need the other settings to set the overscan, dimensions, timings, etc.

I don’t have a Raspberry Pi 4 (or DLP2000 EVM) to test with, so I don’t know exactly what settings you need.

#71

Hi Mick,
Can I connect the pi zero W projector to a smart phone using Bluetooth to be able to project it’s screen? or i can only project the PC desktop screen only?

thank you for your reply in advance.

#72

Hi Guys,
so my problem is that I can’t access the link. It says that the access was denied…
Deckonym

#73

Hi, my links don’t work either and it has been months since Mick’s last video…

1 Like
#74

I found a (kinda) solution with Rpi4 on the TI forum. It has to do with a slightly different i2c timing setting in /etc/rc.local and a slightly different res in /boot/config.txt Thanks to mickmake PhilE Vanderbosh icb and especially Maxim for helping me get to this point.

https://e2e.ti.com/support/dlp/f/94/t/850392

#75

same here man! trying from almost 2 days now!

#76

same here man! trying from 2 days