800x400 HDMI screen not working out of box

[Anonymoose05]

I recently received a 7" 800x400 HDMI screen via order 2727988 and the screen doesn't seem to be working out of the box, see below. After plugging in the HDMI cable the screen starts black and then fades into white and ends up like the picture below. Is this screen damaged?

[mikeysklar]

Which adafruit product id# are using? We have 4 of these.

[adafruit2]

what is it plugged into?

[Anonymoose05]

Part number is 2406.

[adafruit2]

we mean, the computer - what kind/OS :)

[Anonymoose05]

I've tested it on multiple devices, both Linux (CentOS 7) and Windows 10. I've tried output from a dedicated GPU (Quadro P2200) and onboard graphics, HDMI and VGA with an adapter but still get the same result.

[mikeysklar]

Do you have a Pi you can try?

https://learn.adafruit.com/adafruit-5-8 ... -pi-config

Our example config.txt:

Remember, the TFP401 driver does not have a video scaler! If you don't feed it exactly 800x480 pixels the image will not stretch/shrink to fit!

Code: Select all

# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1

# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
#disable_overscan=1

# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16

# uncomment to force a console size. By default it will be display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=720

# uncomment if hdmi display is not detected and composite is being output
hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (here we are forcing 800x480!)
hdmi_group=2
hdmi_mode=87
hdmi_cvt=800 480 60 6 0 0 0
hdmi_drive=1

max_usb_current=1
    
# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
#hdmi_drive=2

# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=4

# uncomment for composite PAL
#sdtv_mode=2

#uncomment to overclock the arm. 700 MHz is the default.
#arm_freq=800

# for more options see http://elinux.org/RPi_config.txt

[Anonymoose05]

It does work with a Pi, however I need a USB powered monitor like this that will work with most machines both windows and Linux. Do you stock something similar that would work? I'd also like to return this unit as it's not quite what I was looking for.

[mikeysklar]

This 10" Pimoroni might be an option as the resolution is a standard 1024x768 that an OS can handle. It is USB based, but it will draw close to 2A.

https://www.adafruit.com/product/4337

You can e-mail [email protected] with your order# and provide this forum thread link to start a replacement order.

[adafruit2]

@anony - sorry for the delay, holiday breaks took over! please email support@adafruit to RMA the screen, it should appear on a Windows box