[Arm-netbook] Doubt about USB in EOMA-68.

[Miguel Garcia]

Hi all,
I've been looking at this:
http://elinux.org/Embedded_Open_Modular_Architecture/EOMA-68#Table_of_EOMA-68_pinouts

Are all EOMA-68 obliged to have 2 USB 2.0 (the first on pin 30 and 64,
the second on pin 34 and 68)?

If in the future there is a EOMA-68 compatible with USB 3.0, would
this USB 3.0 be associated with the first USB 2.0 or the second USB
2.0?

We want to use the USB 3.0 to create a USB 3.0 port (with the current
EOMA-68 only be compatible with USB 2.0, but we want to be compatible
in the future with USB 3.0) and use the other USB 2.0 to connect
internally the WIFI, the BT, the USB IC audio .... And we do not want
that, in the future, some new EOMA-68 be incompatible with this
because we have chosen the wrong USB.

Thank you.

[Luke Kenneth Casson Leighton]

Post by Miguel Garcia
Hi all,
http://elinux.org/Embedded_Open_Modular_Architecture/EOMA-68#Table_of_EOMA-68_pinouts
Are all EOMA-68 obliged to have 2 USB 2.0 (the first on pin 30 and 64,

*correction* ....and optionally 20, 21, 54 and 55:

* 20 ---- not used ---- / USB3 StdA_SSRX-* 54 ---- not used ---- /
USB3 StdA_SSRX+
* 21 ---- not used ---- / USB3 StdA_SSTX-* 55 ---- not used ---- /
USB3 StdA_SSTX+
* 30 1st USB2 (Data+)* 64 1st USB2 (Data−)

....

Post by Miguel Garcia
the second on pin 34 and 68)?

... which is the 2nd USB port and will remain absolutely at the
maximum of up to USB 2.0 because there are only 2 pins available:

* 34 2nd USB2 (Data+)* 68 2nd USB2 (Data−)


answer: you misunderstand the spec.

there must be 2 USB ports *of any type*, absolute minimum is USB 1.0,
with upward-compatibility *required* up to the absolute maximum
possible capability of the card's hardware.

so the TI OMAP35xx series *MAY NOT* be used (directly) because they
ONLY support USB 2.0 480mbit/sec.

Post by Miguel Garcia
If in the future there is a EOMA-68 compatible with USB 3.0, would
this USB 3.0 be associated with the first USB 2.0 or the second USB
2.0?

first. always and only the first. that should be clear in the spec.
it is at least implicitly clear because the first port pins (6of) are
only available for USB3, whereas the 2nd is only 2 pins (USB2)

Post by Miguel Garcia
We want to use the USB 3.0 to create a USB 3.0 port (with the current
EOMA-68 only be compatible with USB 2.0, but we want to be compatible
in the future with USB 3.0) and use the other USB 2.0 to connect
internally the WIFI, the BT, the USB IC audio .... And we do not want
that, in the future, some new EOMA-68 be incompatible with this
because we have chosen the wrong USB.

... which is exactly why it won't change. basically once the first
hardware is out, the spec is "nailed" for ... well... forever. which
is why it's good to have caught the things we have in the past couple
of months.

l.

[Miguel Garcia]

Post by Luke Kenneth Casson Leighton
... which is exactly why it won't change. basically once the first
hardware is out, the spec is "nailed" for ... well... forever. which
is why it's good to have caught the things we have in the past couple
of months.

So we have to use the first USB (20, 21, 54, 55, 30 and 64) for a
external USB 3.0 port, and use the second USB (34 and 68) to connect
internally (by a HUB USB IC) the WIFI, the BT, the USB IC audio...

Is that better?

Thanks.

[Luke Kenneth Casson Leighton]

Post by Miguel Garcia

Post by Luke Kenneth Casson Leighton
... which is exactly why it won't change. basically once the first
hardware is out, the spec is "nailed" for ... well... forever. which
is why it's good to have caught the things we have in the past couple
of months.

So we have to use the first USB (20, 21, 54, 55, 30 and 64) for a
external USB 3.0 port,

typically base boards would put a USB 3.0 port and USB 3.0 hub down
*IF THEY WANTED TO*.

if however the designers of base boards wanted to do a simpler
lower-power lower-cost board that did not need USB3 or was not
expecting to have high-speed peripherals etc. then you could ignore
the 3.0 lines entirely and put a 0.5 watt power supply IC down.

Post by Miguel Garcia
and use the second USB (34 and 68) to connect
internally (by a HUB USB IC) the WIFI, the BT, the USB IC audio...

yeahhh pretty much. or 3G modems and the like. keyboards. mice.
anything where you can expect it to be low-ish speed.

Post by Miguel Garcia
Is that better?

yeah.

Post by Miguel Garcia
Thanks.
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