Questions About UART Accessibility

[Oleksij Rempel]

Am 29.12.2013 05:03, schrieb Linus Lüssing:
> Hi!
> 
> I'm currently looking into getting a serial interface to an
> ath9k_htc based USB wifi stick working.
> 
> I found the very useful wiki entries on wikidevi.com [0][1] which
> Oleksij had been suggesting earlier on this mailing list. This is
> probably a beginners question, but I'm wondering what "accessible
> UART" actually means. Does it mean for instance that the TP-LINK
> TL-WN722N, which is not listed in the "accessible UART" section,
> doesn't have any PINs for UART, not even directly on the PINs of
> the chip? Would I be better off getting my hands on a different
> device for development purposes?

It means, the pin on the chip is not soldered to the board, or do not
have any accessible pad for it. It is just harder to solder :)

> I'm especially glancing at the Ubiquiti Networks WiFiStation EXT
> [2]. Am I right in assuming that J4 [3] is actually providing a
> much easier to access UART, with a lot less/easier soldering work?

yes

> Thirdly, adf_os_print() is probably the debug method for sending
> some output over UART, right? Are there any other interesting
> debugging interfaces you could suggest? There's no interface yet
> for directly, easily printing stuff from the firmware into the
> dmesg output of the host, is there?

yes, there is no method to send it to the dmesg. It will make some thing
easier, but it won't help on usb related issues. So UART still stay the
preferred choice.

There is JTAG on it, but i have no software and idea how to work with
Xtensa CPU. Suggestions are welcome.

If you are in germany i can solder the pins, you will need to pay only
shipping.

> Cheers, Linus
> 
> 
> PS: And thanks for all the work you guys have spent to get this
> firmware open, can't wait to get my hands on its software and play
> a little with it :).
> 
> [0]: http://wikidevi.com/wiki/AR7010
> [1]: http://wikidevi.com/wiki/AR9271
> [2]: http://wikidevi.com/wiki/Ubiquiti_Networks_WiFiStation_EXT
> [3]: http://wikidevi.com/wiki/File:Ubiquiti_Networks_WiFiStation_EXT_board_top_near_MicroUSB_SO.jpg




-- 
Regards,
Oleksij

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 295 bytes
Desc: OpenPGP digital signature
URL: <http://lists.infradead.org/pipermail/ath9k_htc_fw/attachments/20131229/8f425949/attachment.sig>