The display is sold as compatible with Raspberry Pi and probably it is but it didn’t work out of the box. The box comes with a CD-ROM but I don’t have any way to read that old stuff anymore. The landzo.com website doesn’t seem to host the content of that CD-ROM either.
The Pi doesn’t use the correct video modes for the display out of the box so I had to read the documentation. The gist of it is that you need to add a new custom mode to /boot/config.txt as below:
# uncomment to force a specific HDMI mode (this will force VGA) hdmi_group=2 hdmi_mode=1 hdmi_mode=87 hdmi_cvt=800 480 60 3 0 0 0
If you’re interested, here is how I got to those numbers. I rebooted the Pi in VGA mode (hdmi_group=1 & hdmi_mode=1) and then ran the tools to interrogate the display:
pi@raspberrypi:~ $ /opt/vc/bin/tvservice -d edid.dat Written 128 bytes to edid.dat
Parsed the file with the edidparser:
pi@raspberrypi:~ $ /opt/vc/bin/edidparser edid.dat Enabling fuzzy format match... Parsing edid.dat... HDMI:EDID version 1.3, 0 extensions, screen size 15x10 cm HDMI:EDID features - videodef 0x80 !standby !suspend !active off; colour encoding:RGB444|YCbCr422; sRGB is not default colourspace; preferred format is native; does not support GTF HDMI:EDID ignored unknown descriptor tag 0x10 HDMI:EDID ignored unknown descriptor tag 0x10 HDMI:EDID ignored unknown descriptor tag 0x10 HDMI:EDID does not yet know monitor vertical range, setting to default 24 to 120Hz HDMI:EDID failed to find a matching detail format for 800x480p hfp:40 hs:48 hbp:40 vfp:13 vs:3 vbp:29 pixel clock:32 MHz HDMI:EDID calculated refresh rate is 66 Hz HDMI:EDID guessing the format to be 800x480p @70 Hz HDMI:EDID found unknown detail timing format: 800x480p hfp:40 hs:48 hbp:40 vfp:13 vs:3 vbp:29 pixel clock:32 MHz HDMI:EDID established timing I/II bytes are 00 00 00 HDMI:EDID standard timings block x 8: 0x0101 0101 0101 0101 0101 0101 0101 0101 HDMI:EDID adding mandatory support for DMT (4) 640x480p @ 60Hz HDMI:EDID filtering formats with pixel clock > 162 MHz or h. blanking > 1023 HDMI:EDID no known preferred format has been set HDMI:EDID filtering preferred group has been changed from Invalid to DMT HDMI:EDID best score mode initialised to DMT (4) 640x480p @ 60 Hz with pixel clock 25 MHz (score 0) HDMI:EDID best score mode is now DMT (4) 640x480p @ 60 Hz with pixel clock 25 MHz (score 36864) HDMI:EDID preferred mode is updated to DMT (4) 640x480p @ 60 Hz with pixel clock 25200000 Hz HDMI:EDID has only DVI support and no audio support edid_parser exited with code 0
From there I saw this interesting line:
HDMI:EDID guessing the format to be 800x480p @70 Hz
I know the display’s resolution is 800×480 so that has to be my clue for the new mode. The docs gave me the rest.
hdmi_cvt=<width> <height> <framerate> <aspect> <margins> <interlace> <rb> Value Default Description width (required) width in pixels height (required) height in pixels framerate (required) framerate in Hz aspect 3 aspect ratio 1=4:3, 2=14:9, 3=16:9, 4=5:4, 5=16:10, 6=15:9 margins 0 0=margins disabled, 1=margins enabled interlace 0 0=progressive, 1=interlaced rb 0 0=normal, 1=reduced blanking
The next challenge is to enable the touchscreen: the driver is probably in the CD-ROM and I haven’t found it online yet.
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