After writing about little touchscreens for the Raspberry Pi (TinyLCD, AliExpress LCD), the official Raspberry Pi Touchscreen, now a post about HDMI monitors. I have several now and each has it pros and cons. As usual, the one you use will be dependent on the project and it is nice to have choice.
Note that there is always an extra facility to control the Raspberry Pi comfortable from behind the large screen and professional keyboard of my PC on my desk, once network is available: SSH and PuTTY for the commandline, and XRDP for the desktop for programming, see here how to use that.
These are the monitors I use with my Pi’s, connected via HDMI:
- 9 inch HDMIPI monitor
- 7 inch LCD screen, bought from ebay, AT070TN90
- 19 inch LG Television FLATRON M197WD
- DELL monitor 17 inch
- HP Monitor 15 inch
- IIyama Prolite X82483HSU 22 inch
- inch LCD HDMI Touch Screen Display TFT LCD Panel Module 800*480
- And one via compostite: 5 Inch TFT LCD Car Rear View Monitor
As you can see from small, 5 and 7 inch, to quite large!
Support a particular screen format
A standard HD HDMI monitor works fine on the RPi, in 1920×1080 pixels native format. But these smaller screens have lower resolutions and the reuslting image looks bad. So every monitor for an optimal picture, requires some simple adaptations in the RPi configuration file /boot/config.txt.
For a good description of the entries in the config.txt see the Elinux site and on here the Raspberry foundation site.
First some entries to have a better understanding of, edit the file with care and reboot after changes made. It may be handy to have SSH network access, since the screen may not give a useful picture when experimenting with the settings.
sudo nano /boot/config.txt # uncomment if you get no picture on HDMI for a default "safe" mode #hdmi_safe=1 # uncomment if hdmi display is not detected and composite is being output #hdmi_force_hotplug=1 # uncomment to increase signal to HDMI, if you have interference, blanking, or no display #config_hdmi_boost=4
tvservice -d edid edidparser edid
Study the output, determine group and mode (CEA, DMT) and add the following lines, as shown in the description for each monitor to the end of your config.txt and check all the other HDMI/SD settings not to be active!
A 9 inch HDMI monitor, developed and sold via a kickstarter campaign by Alex Eames (of Raspi.tv fame, see also his RasPIO Duino product) and Cyntech (who did the actual production and shipping). Still available on Raspberry Pi webshops and from Cyntech. 1200×800, shiny acrylic case, 2x HDMI input, VGA optional. Gives sound output!
I did not add a Raspberry Pi ‘inside’ but use it as a monitor . A DIY package, mine came with broken inside panels, some superglue overcame this invisible. My delivered driver board was broken, and replaced without problems.
For my HDMIPI it was necessary to add “hdmi_ignore_edid=0xa5000080” in Buster.
Good picture, though the reflective mirroring and slight diffusing effects of the acrylic in front of the screen can be annoying in daylight. Handle with care to avoid scratches.
Nicely documented on http://hdmipi.com/.
(yes, that is my hand holding the camera!)
# HDMIPI 1280x800 60 Hz hdmi_ignore_edid=0xa5000080 hdmi_group=2 hdmi_drive=2 # for alternative modes get sound hdmi_mode=28
Search on e.g. ebay or AliExpress or Amazon for HDMI-VGA-2AV Reversing Driver-board 7 inch AT070TN90 800×480 lcd display.
Good picture, very flexible with HDMI, VGA, and 2 AV inputs. No sound support. Comes as kit, I made with my limited skills a wooden frame.
CVT mode as explained on the Raspberry fora
hdmi_cvt= &amp;lt;width&amp;gt; &amp;lt;height&amp;gt; &amp;lt;framerate&amp;gt; &amp;lt;aspect&amp;gt; &amp;lt;margins&amp;gt; &amp;lt;interlace&amp;gt; &amp;lt;rb&amp;gt; width width in pixels height height in pixels framerate framerate in Hz aspect aspect ratio 1=4:3, 2=14:9, 3=16:9, 4=5:4, 5=16:10, 6=15:9 margins 0=margins disabled, 1=margins enabled interlace 0=progressive, 1=interlaced rb 0=normal, 1=reduced blanking
# 7 inch LCD Display monitor ebay 800x480 AT070TN90 #increase HDMI signal strength (just a black screen if not set!) config_hdmi_boost=4 #remove black borders disable_overscan=1 #set CVT as default hdmi_group=2 hdmi_mode=87 #set specific CVT mode hdmi_cvt 800 480 60 6 0 0 0
# LG and HD ready Philips TV DMT mode 28 1368 x 768 (which is scaled to 1200x800!) hdmi_group=2 hdmi_mode=28
General purpose PC monitor, 1280×1024. Connected via HDMI to DVI converter.
Excellent sharp picture, though not widescreen.
#DELL DMT mode 35 1280x1024 hdmi_group=2 hdmi_mode=35
Small 15 inch monitor with audio, DVI and VGA. Connected via HDMI to DVI converter. Has an analog audio input!
Excellent picture, though not widescreen.
# HP1530 1024x768 DMT mode 16 hdmi_group=2 hdmi_mode=16
See this 7 inch monitor for settings7 inch LCD screen, bought from ebay, AT070TN90
A very cheap ($17 including shipping) and small display. Only composite. Works fine on the Raspberry Pi all models. The console is mediocre, the desktop is not bad at all. Not recommended though, but handy to test composite and an occasional view.