RPi3+ blues

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I have been working a few days improving an existing project based on a Raspberry Pi. It is a art piece with a vertical plotter that draws lines on with a pen. Software and data were already developed and I was just adding some finishing touches.

I was given a new RPi3+ board to upgrade the system but when I connected the new board with the existing SD card the system did not boot up. As our system did not include an HDMI display but an embedded one, we did not have display unless the system could successfully boot. My first thought that then new board could be more power hungry than the existing one and therefore the existing power supply was not enough to keep up with the demand. I had to put back the older board and left the one for further testing.


Once I managed to get an HDMI display connected to the board, I could see the image above. Not sure whether it was some Harry Potter add on the upper left corner or, maybe, someone trying to tell me there was something wrong with the power supply. The red LED on the board was off and there was some blinking pattern on the green LED but no boot.

I read that sometimes this rainbow box could appear for an extended period of time if the input voltage was below 4.65 Volts, but after checking with my meter I could see there were 5.16 Volts so the idea of the power supply not being able to deliver enough power vanished (I am using a 5V 2.5A supply).

A bit more googling brought me to this page, where they are testing a power supply and are getting this same result. But as they explain, the reason is the new RPi3+ needs some new code that may not be present if you are using an older install that has not been upgraded. The doctor recommended one sudo apt update followed by a sudo apt upgrade and that should cure the problem.

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