My A20-OLinuXino-MICRO does not boot any more.
It worked; I successfully configured the network and installed openmediavault.
It stopped working when I tried to power it down when the LiPo battery (BATTERY-LIPO6600mAh) was connected.
It did not power off, so I pulled the power cord.
After that it did not restart any more.
When powered on, the red led lights on, but the green led stays off.
If I connect the LiPo battery, the orange led lights on when the board is powered.
This is what I tried:
- power it on again; I've tried with two good 12V power sources, that's why I don't think the problem comes from the PSU
- reflash the micro-SD card
- use another micro-SD card
- connect an Olimexino-32U4 to get the output from A20's UART0, since I don't have a USB-Serial-Cable-F, but with no result (I could have mistaken the program to make the Olimexino forward serial data)
The behaviour of the board is always the same: it stays silent with its red led on; the A20 heats normally, but the board does not boot.
I think I'll order a USB-Serial-Cable-F to see if I can get any info from the board.
Any suggestions?
Thanks
It is very important that you see the output of UART0. You really should buy USB-Serial-Cable-F. ;)
Otherwise it will be very very difficult to detect the problem.
I tried with the serial cable, but there's no output.
It's a hardware failure.
I've tested the voltages:
5V: 5.4V
3.3V: 0.3V
1.5V: 1.54V
1.2V: 1.24V
IPSOUT: 5.4V
The 3.3V line doesn't work.
It's likely U15 is burnt, or maybe L21.
If you can get to it, check PIN 1 of U15 as this should be HIGH to enable the 3.3V output.
PIN1: 3.26V
Suppose U15 (SY8008C(AA)C) is broken.
What about desoldering it and applying directly the 3.3V I need?
I'm powering my A20-olinuxino with the 12V line of a PC PSU with this board:
http://dangerousprototypes.com/docs/ATX_Breakout_Board (http://dangerousprototypes.com/docs/ATX_Breakout_Board)
I can take the 3.3V from there and apply it to the 3.3V line of the A20 board, once U15 is pulled away.
If it works, I know for sure that I need to replace U15.
The only issue you need to watch in doing this is the power up timing on the power rails as EXTEN is generated by the AXP209 and I am not sure what the effect would be if there was 3.3V before some of the other rails.
You will need to check this before you give it a try.