
Access UART ports - ytch
http://developer.sonymobile.com/knowledge-base/open-source/open-devices/how-to-access-uart-ports-on-xperia-devices/
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kelnos
I'm of two minds on this. On one hand, articles like this seem to indicate
that Sony has become incredibly developer-friendly... but on the other hand,
the recent Xperia phones wipe a DRM partition if you unlock the bootloader,
irretrievably destroying keys that allow a bunch of things not work, such as
some software that makes the camera actually good.

So we're stuck either not unlocking and rooting at all, or waiting for an
(unlikely?) root exploit to be found that allows a custom recovery to be
installed. And even then, running a custom kernel still requires unlocking the
bootloader, so you can't run AOSP or CM, or any of the other mods.
(Fortunately, with a root exploit, you can back up the DRM partition and
restore it later, but still, it's not ideal.)

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rodgerd
> it's not ideal.)

I'd bet good money that at least some of it is patent crapulence and the like.

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DanBC
Sony DRMs _everything_ and has weird media formats on top.

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miander
This is generous of them to provide this information when most manufacturers
are doing everything they can to prevent people from modifying their devices.

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cornellwright
Wow this is way more transparency than I'm used to seeing from Sony. Hopefully
it's not just a one-off thing.

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tw04
They've been focusing on being open on the mobile front for several years now.
I'm still waiting for them to drop their horrible skins and move to stock
android. Or at least make the skins optional. The Z#c line-up is, imo, in a
class of it's own. It's nice to have a phone that's actually small, light,
with a great camera, and amazing battery life. If only they'd ditch the skin!

~~~
sohkamyung
Any comments on Sony's tablet line-up? I'm looking for a replacement for my
now EOL Nexus 7 (2012 edition) tablet and looking for one in the 8-9 inch
category, mainly for off-line reading (ePUB files) and web browsing.

My main requirement is an OS that is getting updates on a semi-regular basis.

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someone755
A 2013 N7 (though that's losing support very soon), a NVidia tablet (the
newest one is a great performer, only $200), Asus ZenPad S 8 (or whatever it
is -- the 2GB RAM variant is great for the price, though updates are iffy).
The Nexus 9 gets updates, but its performance isn't the best, and people say
the build is very bendy.

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sohkamyung
Thanks. I forgot to mention that I live in Singapore. So getting the NVIDIA
tablet or the Nexus 9 locally is difficult (no direct distributor).

I may take a look at the Asus ZenPad.

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kholk
The parameters are 115200, -> 8n1 <-…… Remember to enable kmsg to UART in the
kernel commandline and … personally, I use PuTTY on Linux as well (just give
the right permissions to the tty device you're going to use).

About cmdline parms, note that downstream and mainline DO differ, so take this
as reference: Downstream 3.4/3.10/QC kernels: console=ttyHSL0,115200,n8
Mainline, korg 4.4-rc4 currently: console=ttyMSM0,115200,n8

Aside from this, and if you're a developer you actually should know, here's a
lil cool info: you can also use an Arduino to communicate with your device on
UART…. Just be sure to NOT connect any VCC to the board, otherwise … you'll
have to say goodbye!

Wiring UART is a serious thing and requires soldering experience: use good,
non-conductive flux in VERY SMALL quantities and possibly thin-as-hair
insulated wires.

My suggestion is to fix those wires somewhere in your phone and "export"
thicker ones outside of the phone, practicing a small hole in the housing:
this will make your "mod" to last longer, and will make it "safer" since you
won't be never anymore touching the mainboard with a soldering iron.

That said… this post finally gives wonderful pieces of informations to all of
the very experienced developers out there who want to experiment very new,
wonderful things, opening nearly endless possibilities on Sony platforms.

Also, Sony has got a wonderful open device "section" on their Developer World
website, you may want to check it out:
[http://developer.sonymobile.com/knowledge-base/open-
source/o...](http://developer.sonymobile.com/knowledge-base/open-source/open-
devices/)

...and even if it seems that they are just playing with AOSP, they are
effectively creating a good, sane base with clean code that can be also easily
used for porting/running alternative OSes, like Sailfish, FirefoxOS etc, like
you can see on the Mozilla page here:
[https://hacks.mozilla.org/2015/10/build-and-run-firefox-
os-o...](https://hacks.mozilla.org/2015/10/build-and-run-firefox-os-on-sony-
open-devices/)

So..... hands up for Sony's friendship with the opensource community!

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jonmrodriguez
This seems like it would make Xperia phones a potentionally great platform for
prototyping of IoT devices that would benefit from a cellular radio. The UART
port would be used to connect to a microcontroller which would use protocols
such as I2C, SPI, and SDIO to connect to peripherals.

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Raed667
Just FYI: this is also available for most Chinese Android phones.

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DanBC
Is there a reliable site for reviews of Chinese Android phones?

I'm tempted, but it's hard to know which are good and which are terrible.

~~~
Raed667
You should check the devices made by Tinno Mobile.

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aplorbust
Beta program for custom ROM's:
[http://developer.sonymobile.com/services/flash-
tool](http://developer.sonymobile.com/services/flash-tool)

But it's a Windows .exe. How about other OS?

PS3 is FreeBSD, isn't it?

Hey Sony, how about a BSD "phone"? Even a pocket-sized WiFi device with no
baseband could be very useful.

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ytch
TL;DR: Sony shows how to access UART ports of some Xperia devices

