# Monitor output is always my touchscreen, not my computer monitor

So, I got a Raspberry 3 model B and connected it with a keyboard, a mouse, and a touchscreen. When I connect an HDMI-DVI converter to my Planar monitor, it's fine at the beginning of turning on the RPi. However, my computer monitor stopped loading after some time, like the picture showing here.

Then, my touchscreen works and loads into the desktop, leaving my computer monitor like the picture shows.

I searched on the Internet and tried to modify the code in config.txt. Uncomment the line hdmi_force_hotplug=1

Uncomment the line hdmi_group=2

Uncomment the line hdmi_mode=16

Uncomment the line hdmi_drive=1

But, it still doesn't work. I really don't know what I should do now. I hope you can help me!

• That is by design you get one or the other, I have seen some youtube videos claiming to run both but have not tried it myself. – Steve Robillard Jul 5 '17 at 20:37
• Actually, I don't need 2 screens. I want to show things on my computer monitor. But even I take my touchscreen off, my computer screen still acts like the picture shows. I don't know the reason. – Tian Xie Jul 5 '17 at 20:43

Assuming you are using the waveshare 3.5in. TFT (or a compatible display), You can switch back to HDMI mode with the following commands:

cd LCD-show/
./LCD-hdmi


Then remove the touchscreen and reboot your Pi.

More details can be found on the waveshare wiki.

If your screen came with a prebuilt SD card image or SD card, you will need to switch to the standard Raspbian image. To allow switching between your regular and touchscreen easier I would suggest burning the standard image to a new card. Full details on downloading and burning the image can be found on the Pi Foundation's download page.

It appears you are running Occidentalis (an Adafruit modified version of Raspbian) therefore it is likely you are also using an Adafruit PiTFT (you could confirm this bt looking at the TFT's board, it should have the adafruit logo and name printed on it. The simplest method of switching back to your Planar monitor would be to download Raspbian as mentioned above, and burning a new SD card.

• Thanks! I tried these commands in the Terminal, but it shows that "No such file or directory". – Tian Xie Jul 5 '17 at 23:11
• What touchscreen do you have? How did you install it? How did you configure it? What instructions did you follow? Did the screen come with an SD card? or did you burn your own? If you burnt it yourself what image did you burn (specifically - where did you get it)? what is the output of sudo find / -iname LCD-show? – Steve Robillard Jul 5 '17 at 23:22
• I think the touchscreen is waveshare 3.5in. TFT. But I don't know other details because it was configured by others in our lab long ago. I found that if I take off the touchscreen, the program hangs on with "random: nonblocking pool is initialized". – Tian Xie Jul 6 '17 at 0:15
• And the output of sudo find / -iname LCD-show is nothing, leaving me to input another command. – Tian Xie Jul 6 '17 at 0:16
• I think I could open a new question because I don't need two screens. Now, the problem is: without a touchscreen, my computer monitor hangs on when turning on the power, like the picture shows. – Tian Xie Jul 6 '17 at 0:34