Quote from dsommerfeld on May 18, 2022, 7:03 am

Hi,

that's right. The message comes from the linux kernel. It has no effect of the function, but it looks not really good.  You can disable this:

You must modify the confi.txt file on the davinci and add te following line: avoid_warnings=1

 

You can do this via shell or direct on the sd card.

Then you never get this warning again.

 

Dirk

Quote from Pietro on May 18, 2022, 1:17 pm

Quote from tdavies on May 17, 2022, 9:56 pm

Hello! I recently purchased a Certabo set with a DaVinci and I'm really happy with it. In order to make it more portable I'm trying to run the DaVinci from a portable battery pack, but I'm having issues with low voltage. I've tried a couple of different packs (an Anker one and one from the Raspberry Pi specific one from Adafruit) but they always give me low voltage warnings once the board is plugged in, and when the warning is up I seem to get errors with chess pieces not being detected more frequently. When plugged into a power outlet everything runs fine. I tested with a USB voltage thingy and it shows it running at 5.1V or more all of the time, but maybe the device is not very accurate or doesn't update at a high frequency. Does anyone have any recommendations for either reducing the power draw, or recommendations for power packs that should work ok with a DaVinci? Thanks in advance for any help!

Hi Tom

Welcome to the forum and thanks for your message. As Dirk was pointing out that will disable the warning but i 'm not sure will reduce the power consumption for the unit (Dirk is that reducing the current draw too?).

You are experiencing voltage drop because the DaVinci is asking too much current to power bank thus more power than the power bank is able to provide so what happens unlike when you have plug, because the current is above the possibility the voltage will be dropping below 5V thus the peripheral will also see lower voltage and cannot be proprely supplied. The DaVinci with Pi4 is rated for 3A so need to be sure the power bank is able to provide constantly 3A @5V  means 15W   (Pi3 for example is bit less 2,5A) So please check how much current each port on power bank can provide should be written close to it. Normally there can be two port for 1A and 2.1A or more recent powerbank can have port for 3A for new USB device like DaVinci with USB C connector too. Alternatively you can take a Y cable USB C + two usb A to connect to powerbank  so can connect to both ports of the power bank so the total current will be 2,1A+1A on same line toward the DaVinci. Just make sure you give 3A and power bank you use is rated really for that. So you should not get low voltage message or flickering of red led on DaVinci. Hope this helps

Let us know and take care!

Pietro

 

 

Quote from tdavies on May 21, 2022, 6:15 am

Thank you so much for the responses. I tested the packs I have and they provided pretty low current, so I found one with 3A output and it's working great.  Thanks again!

Tom

Quote from alain on May 21, 2022, 9:07 am

Dear All

 

I had too some issues because of battery pack and careful attention has to be paid to power. the Y cable is mandatory too.

I will add a personnal experience regardings power: you may think that some chessmen recognition  (flashing led or flashing chessmen on screen are due to a low power level (i thought so 🙁  ).

But this issue may occur when a PC monitor is too close to the board.!

Please have nice games ....

 

Alain

Quote from dsommerfeld on May 23, 2022, 6:48 am

Hi Pietro,

the current is not a problem to run a davinci. The warnings are available, because there are 4 USB Ports on a PI, that can provide other USB devices. Then the max current is needed. If you run the davinci standalone, there active currnet is much lower the 1A.

 

Dirk