Intermittent boot failure w/ U-boot
Added by Emmett Bradford about 12 years ago
I have the 1808F on our carrier board now.
It is working and communicating RS232.
About 3/4 of power-on events, it locks up.
There is no RS232 comm, and the FPGA never finishes configuration.
The same SOM on the Industrial I/O board works fine.
Where to start?
I have a MAX3221 RS232 xcvr with the power-save ckt enabled. Maybe this causes a delay.
Would U-boot hang up if it did not see RS232 right away?
Any other ideas?
Replies (3)
RE: Intermittent boot failure w/ U-boot - Added by Michael Williamson about 12 years ago
What do you have for a reset circuit? How is the reset input driven?
U-Boot shouldn't hang if there is no RS-232 activity (doesn't look at flow control or anything). I don't think it uses any kind of BAUD detect either.
-Mike
RE: Intermittent boot failure w/ U-boot - Added by Emmett Bradford about 12 years ago
Here's the SOM sheet, which I believe has everything pertinent to this issue.
U1 is providing a 67ms delay which I'm sure is overkill, but should work OK.
I get the same result w/ power-up or with the reset switch SW1 @ U1.
Also - what are the BUSY and AWAKE LEDs?
When should those be lit?
Thanks,
Emmett
RE: Intermittent boot failure w/ U-boot - Added by Emmett Bradford about 12 years ago
I found the problem.
It was not seating well in the SODIMM socket.
That's a long story, but was my fault.
I am curious though, about which pins would cause that.
Thanks,
Emmett
