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Can't boot; LED flashing
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Posted:
Sun Aug 20, 2017 5:12 am
by rsood
My Parallella won't boot. The green LED indicator which I assume is the one in the documentation that says "controlled by the Zynq GPIO pin" is flashing on and off. Also, the green LED on the power adapter which came with it is flashing. What does this mean? Is it correctable? Any troubleshooting tips?
Re: Can't boot; LED flashing
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Posted:
Wed Aug 23, 2017 4:38 am
by KNERDY
Right next to the Ethernet port, there is a connector with 3 pins sticking out labeled GND, RX, and TX.
You will need to purchase a USB to TTL cable (can get them for about $2-$3 off eBay), and connect the correct PINS from that cable those PINS. The docs with the cable should identify them for you.
Once connect, if you have Windows, look in the device manager for Serial Port, and look which COM# has been assigned to that USB cable you plugged in.
Then use the SSH application Putty, and select SERIAL on the connection type and put COM1, 2, 3, or 4 in the Serial line window and increase speed from 9600 to 115200.
This will connect you to the device as if you are looking at the device from a monitor connected. If it is functioning you will see some text appear in the Putty window. If you don't think the connection is functioning, you can try it on another device like a Arduino.
Re: Can't boot; LED flashing
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Posted:
Wed Aug 23, 2017 2:45 pm
by cmcconnell
Re: Can't boot; LED flashing
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Posted:
Thu Aug 24, 2017 11:13 pm
by rsood
Thanks for the replies; I really appreciate it.
I have not had it working since I posted a couple years ago (obviously this has not been my top priority; not getting any replies to that was also discouraging).
I did get it to boot up a couple times when I first got it; it booted the first time I plugged it in, but then wouldn't boot after I did shutdown -h now. I reflashed the SD card and got it to boot again (although it took a very long time, > 30 min), but then I repeated the process of shutdown -h now, attempt reboot, reflash, and since then I haven't been able to get it to boot.
The power supply issue seems like a promising thing to test out. I'm not sure why that thread didn't come up in my searches before. I may have issues beyond that though, because my ethernet port, which used to light up when it was plugged in even though it wasn't booting, isn't doing so anymore. Oh well, we'll see what happens when the new power supply I've ordered comes in.
Thanks
Ravi Sood
Re: Can't boot; LED flashing
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Posted:
Sun Aug 27, 2017 4:31 am
by rsood
Yep, it was the power supply. Got a new one and now there are no issues booting up or shutting down (except that it seems power doesn't get completely cut to the board - the ethernet port still blinks, and one of the green LEDs on the board is still on - the documentation only mentions one green LED on the board; not sure what the other one is/which is which).
Since this power supply issue was so common, you'd think Adapteva would have issued its own recall...