[MinnowBoard] no suitable video mode found booting in blind mode

[Luca]

Hi,

i've changed the power supply with one with 3A, but it doesn't work.
I've tried also to boot from sdcard with Ubuntu and Fedora but with no
result (Fedora no output, and Ubuntu the same of Debian).
The usb port seems to work only with CDROM, because with usb the key it not
identified in boot list (the key led doesn't blink  when the key is
attached, but the key is working because i've flash with the iso from my
pc). Yesterday i was able to boot from usb key. I've also try to load the
default config in Device Manager->System setup.
I don't know...
Where can i increase the log level?

Thanks,

Luca.


2015-05-21 22:23 GMT+02:00 Ken Tait <ktait at venturesystemdesign.com>:

> John,
>
> The power supply issue is pretty straight forward to me since I deal with
> this all the time. The Wallwarts under load have a slow rise time. This
> tends to fool reset monitors and comparators and results in things not
> sequencing right. They work, but don't all start at the right time as a
> simple explanation. You get around this by using a larger supply, adding a
> switch first, adding some capacitance right at the input jack..not too much
> as this can make it worse.
>
> I had alot of trouble with the minnowboard and just got tired of dealing
> with it for now since there were no lures, but to summarize what i found:
>
> 1.    It didn't seem to like a particular monitor I tried. It was a
> tv/vga/hdmi monitor. The problem was that it was feeding it before it was
> ready and somehow thought it wasn't there, so it locked out this port and
> defaulted to the serial port. If I powered up the monitor first, let it
> sit, then the minnow it would come up.
> The minnow clearly comes up very fast compared to everything around it.
>
> 2.    It didn't always boot cleanly from the sd card, screen messages
> clearly show that it blew past this. This again is a speed issue. This
> particular card probably took a few more MS to initialize than the bios
> allowed. SD cards too are all over the map on spi speed and startup delays.
> Using these same cards on a 800mhz board with angstrom image always works
> fine for comparison.
>
> 3.    I noticed the same thing when I plugged in a USB WIFI, it was hit or
> miss as to whether the bios saw it first time. If if came up at all and
> responded to a keyboard, a manual shutdown and restart always worked
> without un-plugging the stick..
>
> 4.    I have 1 keyboard/mouse pad combo,(GearHead), it REFUSED to see it
> at all. This works fine on 4 other Linux putups I have.Ii think I changed
> the driver in the original image to fix this...can't remember.
>
> All in all, it's clear to me most of the issues are 5V loading and bios
> delay issues.
>
> I don't know how the bios is manufacturing delays, but if you are using
> software delays(bad.bad.bad practice) then they probably are not the actual
> time you think they are or the compiler is optimizing them out. You must
> explicitly tell the compiler with #pragmas to not do this. I experience
> this all the time .
>
> If i get more time, I'll try and get the bios code and take a look at it
> and see if I spot something suspect. Pretty swamped right now...
>
> Ken
>
>
> _______________________________________________
> elinux-MinnowBoard mailing list
> elinux-MinnowBoard at lists.elinux.org
> http://lists.elinux.org/mailman/listinfo/elinux-minnowboard
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.elinux.org/pipermail/elinux-minnowboard/attachments/20150521/eb6b4983/attachment-0001.html>