Rpi Zero 2 W problem with Waveshare Touchscreen

Support Raspberry Pi
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Hi All
The Zero2 W is plugged into

This lcd plugs into both usb ports and the hdmi port.

Will describe how I got there so as to make the problem clear.
Used Timeshift to make a backup of the uSD, then deleted a program I shouldn’t have, so used Timeshift to restore.(Done that many times before on other PC’s)
During the restoration the program showed an error (can’t remember the detail)

So got out my backup uSD and plugged it in.
When I turned on the power, the Rpi cycled through the splash screen and all the .service files, then blanked out and repeated the same thing. Will do that all day.
It never completes the boot process.

Assuming my backup was bad, I re-wrote it with BalenaEtcher and tried again.
Same problem.
So, removed the Zero from the Touch screen and used my desktop monitor.
Everything worked perfectly.

Have tried a number of times,but each time the result is the same.

Now this is not exactly a cheap lcd and until this error I was really impressed with it.
I am open to suggestions as to what to do about this.

Regards

Edit: Have been using this setup for about 3 days before this problem happened.
Just on a hunch plugged the power into the Rpi power supply instead of my desktop USB. Problem solved.

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2

Hi @JW160152 - this sounds like it could be a power issue. Can you show how you are powering the monitor and whether it’s being powered by the same supply as the Pi Zero2 W and what the power supply specs are?

A system photo may help a lot here.

I suspect the Pi is beginning to book, but when the processor load / on-screen content changes the power draw may be overwhelming the power supply. The PSU browns-out. restarting the pi, and then the cycle starts all over again.

3

As a result of that there is only one way to power the combination and that is through the usb C connector on the display.
I did that using a usb connection from my desktop.

But I guess you are correct and as soon as the cpu load goes to it’s max, my port
couldn’t supply enough power.

Now I power it from a rechargeable Lithium usb power module, 10,000mA/hr with max current of 2.5A. It’s about the size of a mobile phone. So far so good.
I can run the Rpi Zero 2W and the display all day without having to charge the battery.

Regards

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