Archive for the 'Tech' Category

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Using the serial port on an Apple Xserve

Some have found my posts on running Linux on the (EFI only) Xserves useful, and one such person is Eddie, who emailed me with some details on how he got the serial port working. Hopefully it will be useful to someone else, so with his permission, the following is what he sent me:

Believe it or not, Apple screwed up the pin-outs on the back of the DB-9 port for the Xserve (it might have been a logic board design error and perhaps they didn’t want to spend the money to re-design it). I made my own null modem cable and got it to work with OS X Server (taking the other end of the null modem cable over to a USB-to-DB9 adapter and then plugged it into my PC running Windows 7). As for how Ubuntu handles serial ports including on Xserves, I have some good news. Today, after much digging around, I found out how this works. First of all the GRUB load / configuration that you helped put together and document for the Xserve recognizes the built-in serial port (hurray!). This built in serial port is recognized as /dev/ttyS0. For example, from my Ubuntu 9.10 kern.log file:

$ cat /var/log/kern.log | grep ttyS
Nov 16 09:34:38 ubuntu kernel: [ 1.140244] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
Nov 16 09:34:38 ubuntu kernel: [ 1.140343] serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
Nov 16 09:34:38 ubuntu kernel: [ 1.140720] 00:09: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A

I’m not sure, however, what ttyS1 is on the Xserve (as you can see in the output above).

Another way to look at this:

root@ubuntu:~# dmesg | grep serial
[ 1.140244] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
[ 1.140343] serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A

Ubuntu specifically made changes to how one goes about configuring from one major version to another (so this is going to also probably differ among Linux distros such as Red Hat) but for what its worth, under 9.10 you have to set up a ttyS0 file and place it in /etc/init/ and the contents should be the following:

# ttyS0 - getty
#
# This service maintains a getty on ttyS0 from the point the system is
# started until it is shut down again.
start on stopped rc RUNLEVEL=[2345]
stop on runlevel [!2345]
respawn
exec /sbin/getty -L 115200 ttyS0 vt102

Once this /dev/ttyS0 file has been created and in place, you can load it like this:

# start ttyS0

which, if successful, should output a line like this:

ttyS0 start/running, process 4478

You can also read the device like this:

# stty -F /dev/ttyS0 -a

and expect output as follows:

speed 115200 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = ; eol2 = ; swtch = ; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R;
werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 hupcl -cstopb cread clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon -ixoff -iuclc -ixany -imaxbel -iutf8
-opost -olcuc -ocrnl -onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
-isig -icanon -iexten -echo -echoe -echok -echonl -noflsh -xcase -tostop -echoprt -echoctl -echoke

I had no problem firing up PuTTY on a laptop running Windows 7 and connecting to the Xserve running Ubuntu. I could log in just as I would be able to at any console whether via KVM or SSH.

Great stuff! Another option to keep our Xserves going into perpetuity especially since Apple is dropping them in a few months!

Anandtech takes a look at AMD’s new “Atom killing platform”

Anandtech takes a hands-on look at AMD’s new CPU+GPU combination platform, Brazos. It’s designed to compete in the low performance power, and mobile spaces.

How well will it perform, especially in comparison to next-gen Atom SOC, Sandy Bridge, or NVIDIA’s ION platform? Not sure yet, but one thing I know, it will be practically useless for Linux without decent driver support.

Update: Looks like some open source drivers are on the way..

I-O Data pays Microsoft to use Linux

Another day, another Microsoft cross-patent licensing agreement for companies who use Linux.

Japan-based I-O Data Device Inc. has agreed to cough up an undisclosed sum to the software giant for using Linux and other open source software applications in its devices and routers.

Now I-O Data joins the ranks of Samsung, LG, Kyocera, Fuji Xerox, Brother and TomTom (and others which we don’t know about).

Microsoft says:

Microsoft has a strong track record of collaboration with companies running Linux-based offerings, and this agreement is a reflection of our commitment to partner with industry leaders around the world.

Thank goodness we aren’t doing anything crazy like deliberately putting Microsoft technologies such as .NET into Linux distributions. That would just be insane.

Amazon, Microsoft sign Linux patent deal

Amazon and Microsoft have signed a patent deal which covers their Linux based products and Kindle.

The deal covers both Amazon’s Kindle product as well as the company’s use of Linux-based servers. Microsoft has maintained that many implementations of Linux infringe on its patents and has signed numerous licensing deals that cover Linux with both companies that sell Linux-based software and those that use the operating system in their hardware.

Faster, better ARM Cortex-A9 on the way

That’s right. ARM is set to take over the netbook market (yay!) and even more good news that their highly successful Cortex-A9 will get a revamp.

Shrinking the die down to 28-nanometer will provide a 40% performance increase and reduce power consumption by 30%. It should be available later this year. Now that will certainly be something for Intel to think about..

Trying to kill Theora – MPEG LA extends royalty free use of H.264 for Internet streaming

So the MPEG LA has extended the royalty free life of Internet streaming H.264 video from the end of 2010 to the end of 2016. The majority of patents expire in 2028, so that will still give them plenty of time to collect on royalties, if we let them.

Make no mistake, this is about stifling the adoption of Theora in order to become the de-facto standard. MPEG LA is trying to kill Theora, but we must not let that happen! We need an open web.

If you use H.264 for ANY OTHER PURPOSE today, you still need a license. Yes, that means you Mr. Linux user ripping your DVD’s to H.264..

Do you use H.264 or MPEG? You need a license.

Recently it was confirmed by the MPEG LA that a license is needed for any use of H.264 and that everyone on the chain is liable. Free software projects are not exempt from this either and neither are end users.

Ben Swartz has an excellent summary about why H.264 should not be used.

A lot of commercial software comes with H.264 encoders and decoders, and some computers arrive with this software preinstalled. This leads a lot of people to believe that they can legally view and create H.264 videos for whatever purpose they like. Unfortunately for them, it ain’t so.

The license that comes with commercial software, such as Apple’s Final Cut Pro, does not cover commercial works. Even so, if you use a commercial software package to create something non-commercial and give it to a friend, they need to be properly licensed also.

You have a license to use their software, provided you don’t make any money, your friends are also all correctly licensed, and you only produce content that complies with the MPEG standard. Using video for a commercial purpose? Producing video that isn’t within MPEG’s parameters? Have friends who use unlicensed encoders like x264, ffmpeg, or xvid? Too bad.

This last thing is actually a particularly interesting point. If you encode a video using one of these (open-source) unlicensed encoders, you’re practising patents without a license, and you can be sued. But hey, maybe you’re just a scofflaw. After all, it’s not like you’re making trouble for anyone else, right? Wrong. If you send a video to a friend who uses a licensed decoder, and they watch it, you’ve caused them to violate their own software license, so they can be sued too.

That’s right folks. Use Handbrake to rip a DVD, or create, view, watch or distribute any H.264 video and you’re liable (royalty free streaming via the Internet has been extended until the end of 2016).

Won’t somebody please think of the children?

Windows 7 killing laptop batteries?

Ars Technica reports on issues with Windows 7 and battery life on some laptops.

These users claim their batteries were working just fine under Windows XP and/or Windows Vista, and others are saying it occurs on their new Windows 7 PCs… their PC’s battery life is noticeably lower, with some going as far as saying that it has become completely unusable after a few weeks of use. To make matters worse, others are reporting that downgrading back to an earlier version of Windows won’t fix the problem.

The issue was originally reported back in June 2009, long before Windows 7 was actually released.

Cheaper SSDs on the way thanks to new 25nm process

Intel and Micron will ship 25nm flash memory in the second quarter of this year, which in turn should finally mean cheaper SSDs for everyone. Yay.

Intel’s existing multi cell X25-M and X18-M models are 32nm. This new shrink enables much greater capacity (8GB NAND measuring just 167 x 167mm) and devices will follow version 2.2 of the Open NAND Flash Interface (ONFI) specification.

With most of the original issues sorted out (or worked around) and the introduction of TRIM, it sounds like SSD might finally start becoming common place in desktops (but I think laptops will see it first).

MPEG LA confirms H.264 license needed for free software and end users

Currently, there is no default video format for use with the HTML5 video tag. The patent and royalty free Theora format was planned to be the default, but this was opposed by corporations like Apple and Nokia. The most popular video format at the moment is the heavily patent encumbered H.264, which is often encapsulated in Flash. As the move to HTML5 gathers steam, the battle for a video format rages on.

The issue of which format becomes prevalent is very important for the future of open web (and especially Linux). Youtube is one of the biggest providers of H.264 encoded media (currently encapsulated in Flash, but there is an HTML5 beta program) and Google will pay hefty royalties for the privilege.

The question of royalties over use of H.264 has become a popular talking point of late, because while Safari and Chrome support it, Chromium (the free software version of Chrome browser) Opera and Firefox don’t.

Now, a discussion on the Linux Weekly News site has answered the question as to whether the MPEG LA will require and enforce free software projects (and developers) to cough up for a license.

The question asked of MPEG LA via email exchange:

I read through the FAQ and can’t find out if Free and Open Source developers and products need to license the MPEG LA patents for MPEG-4 Visual. It was alleged in a comment that royalties are only necessary for products sold, not for free products. Is this correct? Could you please comment on the licensing options for Free (e.g. GPL) and open source implementations of MPEG-4 Visual, specifically h.264? What about downstream users/developers/distributors of Free and open source software?

The answer is a resounding “Yes” and even end users are liable:

In response to your specific question, under the Licenses royalties are paid on all MPEG-4 Visual/AVC products of like functionality, and the Licenses do not make any distinction for products offered for free (whether open source or otherwise)…

I would also like to mention that while our Licenses are not concluded by End Users, anyone in the product chain has liability if an end product is unlicensed. Therefore, a royalty paid for an end product by the end product supplier would render the product licensed in the hands of the End User, but where a royalty has not been paid, such a product remains unlicensed and any downstream users/distributors would have liability.

As an article over at OSNews states, we must ensure that H.264 does NOT become the de-facto standard for video on the web:

“In other words, h264 is simply not an option for Free and open source software. It is not compatible with “Free”, and the licensing costs are prohibitive for most Free and open source software projects. This means that if the web were to standardise on this encumbered codec, we’d be falling into the same trap as we did with Flash, GIF, and Internet Explorer 6.”

I guess it’s up to web developers and corporations to make the smart choice. If Google can purchase On2 Technologies, they might release later generation versions of VP (on which Theora is based) to surpass the quality of H.264.