Flickering screen on Pi Zero W
I am very new to this, having bought my first Pi last week so may be missing something obvious...
anyway, got one of the new Pi Zero W today and did my first proper 'install' - i tried using a readymade image but that didn't work so installed a Raspbian Jesse Lite and installed RP over the top - bit of a faff as i didn't know how to setup the wifi etc, but got there in the end!
Trouble is, right from the start i have suffered from the screen constantly blanking out or flickering, seemingly whenever the pi is trying to do something. After much research i have changed the config file to boost the hdmi (up to 11!) and it seems to have made a slight difference but it is still unusable. The problem still occurs even when nothing is plugged into the usb socket, and plugging either a joypad or keyboard in does not change the frequency of the dropouts.
I am using the same power supply i was using with my Pi3 and had no problems with that at all so don't think that is the issue - unfortunately my multi-meter is broken so cant check voltages on the pi itself.
Given that i thought the zero had lower power-supply demands than the 3 i would be very surprised if that is the issue so any and all advice would be appreciated!
obsidianspider last edited by
What kind of HDMI cable connection are you using? An adapter with a cable plugged into it? What resolution is the TV? You shouldn't have to do anything funky with at Zero to get it to work with HDMI, but I don't have a Zero W. (yet)
it is the same hdmi that i use with the Pi3, but this time plugged in via an adapter (I have ordered a hdmi-minihdmi cable which should hopefully be here in a couple of days.
The tv resolution is 1920x1080p (it upscales to 4k i think as it is a new 65" job) - i will try on my old 1920x1080p tv later today hopefully.
obsidianspider last edited by
@chubsta If I recall correctly the Zero will try to output 640x480 (even over HDMI) by default. I had that issue with mine, now that I'm thinking back. I'm looking through my notes to see how I addressed that and will post back.
Small update - by enabling hdmi_safe=1 in config.txt I get a stable image on the TV, but of course the resolution is very poor.
i guess from this it means the power supply can be ruled out as a problem, and i would also guess the hdmi cable is ok too as it is one i have removed from my PS4 which displays 1080p no problem...
obsidianspider last edited by obsidianspider
hdmi_force_hotplug=1 hdmi_drive=1 hdmi_mode=16 disable_overscan=1
hdmi_mode=16is 1080p. What I'm not sure of is how it would handle being plugged into a 720p screen, but if that's not a concern, then you should be ok.
Here's a link with all sorts of settings that can be put in
config.txtand their meanings.
Well, I wont say this is solved but it is not a problem anymore - I connected the Pi0 to a different tv (51" 1080p) and it works fine, there is no flickering at all, fortunately for me this is the tv that the Pi will be connected to permanently, i was only using the other TV as it was more convenient when setting stuff up!
I guess there is the possibility that the original TV, being 4k, may have been trying to upscale the Pi signal, causing the flickering? Anyone any experience or knowledge of this?
Tina last edited by
Hi, I had a similar problem. It appears I have solved it by forcing the monitor to use HDMI input in the settings as opposed to autodetect. Hope this helps people encountering this issue in the future ;D