[Arm-netbook] SHIPPING!: EOMA-68 Micro Engineering Boards

[luke.leighton]

On Sun, Aug 11, 2013 at 8:17 PM, Christopher
<christopher at firemothindustries.com> wrote:
> Given the issue with the uarts, Is it too far fetched to consider the differential pairs got swapped? (I.e. pin 68 isn't actually going to SATA B- and so on...) I know all the pins on the MEB match the PCMCIA connector. But perhaps the 68pin on the cardedge is misrouted on the a20 card. (Which would require soldering as you mentioned. )
>
> Also, everyone might want to look at their card edge connectors on the a20 PCB. Tried booting up one of mine and it worked and then halted. Looked at the connector and saw pin 66 and pin 33 were slightly bridged (tiny tiny blob of solder was in a peak pointed at the connector )

 ok i think i got it.

 http://www.elecraft.com/Apps/caps.htm
 http://hands.com/~lkcl/eoma/a20_sata/cb_sata.png
 http://hands.com/~lkcl/eoma/a20_sata/sata_conn_sch.png

according to that elecraft link, "103" is 10nF (0.1uF).  someone's
changed that to "103pF", without authorisation... and without telling
us it had been done.  again.  the number of unauthorised modifications
to the schematics by the design house... i'm just... blown away.

 *sigh*.

 ok.

 luckily this means that no PCB mods are required: just a trip to a
SMT house that can do 0402 components (by hand).

 can i ask people to check something: could someone please take a
close-up hi-res photo of the 68-pin connector, TOP side, near pin 56?
 http://elinux.org/Embedded_Open_Modular_Architecture/EOMA-68#Table_of_EOMA-68_pinouts

 you should see a big capacitor nearby.  then two very thin tracks
that appear to come out from under the capacitor (those are the UART
TX and RX).  if the connector's on the left of the picture, then above
those two thin tracks is one of the 5.0v power pairs, and below the
two thin tracks should be one slightly thick track (that's pin 56 -
the ethernet feedback / transformer link).

 l.