HDMI to Vga not working


#1

Hi, we bought our son a Raspberry Pi 3 starterkit for Christmas and unbeknown to me the monitor I bought didn’t have HDMI - I have got the Pi Hut HDMI to vga adapter but the monitor keeps flashing everytime he clicks the mouse…

Can anyone help??? please…?


#2

Correct resolution for that monitor set?


#3

How do I do that…?


#4

I’ll have to have a look and get back to you.


#5

I guess you have to look at, and maybe edit, your config.txt file? That’s lame? Google says there should be an Advanced options in raspi-config, but I’m not seeing it?


#6

Pi Hut have some instructions/debugging steps documented here: https://thepihut.com/blogs/raspberry-pi-tutorials/34512708-troubleshooting-a-raspberry-pi-hdmi-vga-adapter

There’s a table of screen resolutions at the bottom, and you should be able to find the correct one from where you purchased the monitor, or from the box/specifications.

If it’s “HD” it’ll be 1920x1080

If it’s “HD Ready” it’ll probably be 1360x768 but could also be 1280x720

If it’s a computer monitor it could be anything, but is most likely to be 1920x1080 - aka 1080p - these days.


#7

Thank you - I have no idea what the config.txt file is - we are complete beginners!!!


#8

You’ll need to either take the SD card and place it in another computer to work on- in which case you’ll see a drive called “BOOT” pop up, with config.txt on it, or run “Terminal” on your Pi, which you can find like so:

And then type sudo nano /boot/config.txt to start editing the file.

Hit the down arrow 'til you get to the bottom, and add in the config lines you need.

Then hit Ctrl+X then Y and Enter to save and exit, and then reboot.

Do you now what resolution your monitor might be? Or have the brand name/model so we could look it up?


#9

This is the best forum ever! The monitor is HP L2045w 20” widescreen LCD monitor if that helps…


#10

The HP L2045w has a resolution of 1680x1050 according to the specifications. Which means the following added to the bottom of your /boot/config.txt may send it the right signal (although the VGA adapter can add a spanner in the works):

hdmi_ignore_edid=0xa5000080
hdmi_drive=2
hdmi_group=2
hdmi_mode=58

It looks like it has a DVI-D connector in the back, too, under certain circumstances it’s possible to get an HDMI->DVI cable or adapter that will fit that port.

Here’s the adaptor we sell: https://shop.pimoroni.com/products/hdmi-to-dvi-adaptor

Do you see a port on the back of your monitor that would fit this adapter? Pay careful attention to the pins, it should look at least like this- with the little slot on one end:

If all else fails with the VGA adapter, then I believe this should work as long as the port in the monitor has that slot, ie: is keyed for the adapter.


#11

Indeed - the monitor has this port! Would the suggested adaptor still require me coding something…?


#12

Possibly but there’s still a chance it could require similar settings. It’s difficult to tell without testing the exact monitor. It’s definitely worth adding the above into /boot/config.txt first and seeing how it goes first.


#13

My coding career starts first thing - thanks for all the help!


#14

Good luck! Let me know how it goes.