M5 Core seems to work but display stays black

M5Hans

The display of my two month old M5 Core with FW 1.7.0 remains black. When I upload the chess sample I can hear the beeps and there is the expected output through the serial monitor. But never output to the screen, no matter which other sketch I use.

The software and driver used on the PC seemed okay, as everything works fine with a different M5 Core.

Is my M5 Core faulty or does someone have a solution to this problem?

MohamedWasheem

I had a similar trouble earlier, you could try loading in an example which displays something on the screen to test it! I tried loading and running the screen test example, that helped me

MohamedWasheem

I had a similar trouble earlier, you could try loading in an example which displays something on the screen to test it! I tried loading and running the screen test example, that helped me

felmue

Hello @M5Hans

M5 Core (A) display remains dark and M5 Core (B) works fine is a bit ambiguous as over time M5Stack produced multiple devices, for instance:

M5Stack (Base, Gray, Fire) share one hardware platform
M5Core2 uses a slightly different hardware configuration

So if in your case M5 Core (A) and M5 Core (B) are the same type of device, lets say both M5Stack devices, then I'd say one of them is faulty.

However if the working one is an M5Stack variant and the one with the dark display is an M5Core2 then I'd say the issue is that the chess sample has been compiled for M5Stack which doesn't work for M5Core2 without recompiling.

For instance using Arduino IDE, M5Stack requires an include file called M5Stack.h whereas an M5Core2 requires an include file named M5Core2.h.

What is the exact type of the device with the black screen?
What is the exact type of the device that works?
How are you installing the chess sample?

Thanks
Felix

M5Hans

Thanks for your comments! I use two identical M5 Core (light) gray and installed the chess program on both devices via M5Burner. But it also goes wrong with other programs, not only with the chess program (photo).

It doesn't matter if I flash with M5Burner or upload (a simple sketch) via Arduino IDE while M5Stack.h was included, the display remains off but the program is running because there is sound coming from the speaker.

As suggested I ran the display demo program but unfortunately that didn't help either.

felmue

Hello @M5Hans

ok, thanks for the clarification. It looks to me that probably the LCD or backlight is defective in that unit. Maybe ask the store you got that unit from for a replacement?

Thanks
Felix

M5Hans

@felmue

Dutch reseller TinyTronics (http://tinytronics.nl) was so kind to replace the M5Core for free without any discussion and even without shipment costs!

madaerodog

Hello,
the same thing happened to mine also, any idea what to try next? I have a M5Core2.
I am not able to return it for a change.
I have tried uploading the firmware, I hear the sounds of the factory default demo, and the touchscreen works(I hear the sounds of the demo when touching). But it does not display anything.
Thank you,
Constantin

madaerodog

This post is deleted!

felmue

Hello @madaerodog

just to clarify. Has the display worked in the past? Or was it dead from the beginning?

Thanks
Felix

madaerodog

Hello Felix,
Yes it had the factory default code with the vivid animations and it worked fine, I uploaded the UiFlow code and that worked as well, then I tried out some Arduino IDE examples and upon upload, it went black and did not revert not even when completely doing the factory reset with the M5Burner. It does upload the demos and seems to boot and do the thing but it just does not show anything anymore.

Does the display have any internal memory or something that I could erase?

Thank you,
Constantin

@felmue said in M5 Core seems to work but display stays black:

rdware configuration

So if in your case M5 Core (A) and M5 C

felmue

Hello @madaerodog

no, afaik the display doesn't have any internal memory that would need erasing.

I am afraid something got broken or dislodged within your M5Core2, but since you wrote you won't be able to return it, the only thing that comes to mind you could try is to remove the small little white board labelled CORE 2, unscrew the bottom and disconnect the battery. Then try w/o battery and only with USB plugged in.

Note: be careful when removing the bottom as the battery is taped to the bottom but plugged into the main board.

Good luck!
Felix