I installed latest Linux Debian Jessie to A20-OLinuXino-MICRO. It works fine, but when I connect power cable then HDMI screen is automatically off. Board continues to work. USB and battery power source doesn't have this issue. Does anyone know why?
An image from Olimex?
If not, did you report the problem to wherever you got it? (And if not, make sure you do.)
John
Yes, I installed an official image from Olimex for NAND board as I have 8 Gb NAND memory: A20-OLinuXino-MICRO Debian Jessie with kernel 3.4.103+ release 15.
Linux A20-OLinuXino 3.4.103-00033-g9a1cd034181a-dirty #44 SMP PREEMPT Fri Mar 10 08:50:33 EET 2017 armv7l GNU/Linux
What happens if you do the connections in different order - first HDMI then power? Can you measure voltage under the power jack before and after connecting the HDMI? Can you measure voltage between HDMI cable connector shielding and the shielding of the on-board HDMI connector as explained here: https://olimex.wordpress.com/2014/01/22/bevare-non-grounded-tv-monitors-can-damage-your-olinuxino/ ?
By the way, do you have SERIAL-USB cable attached? What does the log show? Can you try disconnecting the SERIAL-USB cable while testing the HDMI?
More powerful power supply solved the issue 12V 2A, before I used 12V 1.5A.