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Installing Debian on Agestar without serial port

I have prepared a firmware and tutorial to Install Debian here, this time without the need for serial port. I have tested this, and it seems that everything works. But of course I will not be responsible if anything happens. If you think there are some missing, unclear or inaccurate steps, or if you doubt about something, then don’t install it. If you have anything to ask just email to yohanes [at] gmail.com, or just post your questions as comments.

NOTE: the web update method only works on agestar ncb3ast, other models can work by using serial port and latest patch for kernel source (2.6.29 or later).

New Firmware Progress

My wife agrees that I can buy another Agestar to hack and use the other one for our network storage. With this new Agestar I can continue my hacks. Currently I am working on building a firmware that can be used to install Debian without serial port. On the first stage, I will build a generic firmware without automatic installer, so the user still needs to do some manual steps to install Debian. So it is something like the manual Debian install on NSLU2 (http://www.cyrius.com/debian/nslu2/unpack.html). Actually because this is generic command line, you would be able to install Gentoo or something else. The next step would be to make an automatic installer like in NSLU2(http://www.cyrius.com/debian/nslu2/install.html).

The main reason why I started with manual installer is because I am not yet familiar with the Debian installer. Currently the manual installer is almost complete, I just need to test it thoroughly to make sure that this will really works without serial port. I hope I can release this in the next few days (or this weekend at the latest).

Fixing Space key on EEE PC

I bought the Eee PC 4G last week, but I haven’t used it optimally. Today when trying to write a new blog post using Eee PC, I felt that the space key is very difficult to press. After searching around, I found out that many people experience the same problem. Surprisingly it is very easy to take of the Eee PC keyboard. Just press on the three dots on top of the keyboard using screw driver, and it will pop out.

Fixing it quite easy, I used a tape to make the space key thicker and easier to press, and I put a tape also in the keyboard to keep the rubber part from moving.

You can see more pictures on my photo gallery.

Reverse Engineering Linux Kernel Image and Modules

I have switched my mind from doing the kernel porting to some other activities, which is reverse engineering ARM binaries for Symbian platform. When just starting, I thought to my self: why don’t I try to reverse engineer the original Agestar firmware, and may be I can complete some drivers for STAR STR9100. So I did, and I can get the watchdog function to work (at least I think it works).

zImage and bootpImage are compressed kernel image, this is compressed by using GZip method 8. The easiest way to decompress it is to give it to gunzip. I just searched the kernel image for the sequence 1f 8b 08, and cut it using khexedit. You don’t have to find where the compressed data ends, gunzip will ignore trailing garbage.

Continue reading “Reverse Engineering Linux Kernel Image and Modules”

How many of you are using STAR 9100 based NAS?

As listed on one of my previous posting, STAR 9100 (to be precise STAR 9104) is being used in these devices:

Coolmax CN-570 http://www.smallnetbuilder.com/content/view/29899/75/1/3/
NS-348S http://www.multicase.de/en/products/76/ns348s.html http://www.enclosureservice.com/
Emprex NSD-100 http://www.emprex.com/02_products_02.php?id=205
Agestar NCB3AHT http://www.agestar.com/english/products/ncb3aht.asp
http://shenztech.com/code/ui/product/product.aspx?prdid=NAS2&subcatid=9
revoltec rs049

We can see from the boot log that says the machine is STAR_STR9100. Lately I have worked less and less on this device, because it has been running smoothly enough for me (I have run it continuously for a week). The last few parts is not so important for me. These four parts are RTC (turns out to be a very limited RTC), LED (only one LED inside the box, which is not very useful), and button (I have never used the button anyway), and Watch dog (this one might be useful, but I don’t have any documentation about this).

I am planning to stop further development. I was planning to build a custom firmware, but I think a full Debian distro is much better for me. But, if there are quite many people that uses this devices and are expecting something like NSLU2 (easy installer, etc), then I might continue the development. So, If you are using Agestar or agestar like devices, please leave a comment, and let me know what you expect.

If I am going to continue the development, I will need to buy another box, because I am currently using this one extensively for my daily activities. Irina (that is the name I gave to my NAS box) is now serving MP3, serving web page, and act as a download station.

RTC on STR9100

I have spent many hours to work on the RTC part, and I decided to give up for now. I have been able to activate the clock, set the clock, and make it run. But the RTC is not useful. First, it is not battery backed, so when you turn off your device, it will not keep the time. Second, it can store only the seconds, minutes, hours, and day of the month. The problem of not having a documentation is sometimes you get stuck, and don’t know what to try next.

There is one feature that is supposed to be useful if I can make it work: the alarm capability. With alarm, some cron-like applications can set to be notified when a particular time comes (it will ease the CPU burden). As far as I know, the cron daemon doesn’t use this feature, so it is not a great loss.

There is one thing that still puzzles me. The original firmware uses X1205 through an I2C bus. From my understanding, the X1205 have different abilities compared to the STR9100 RTC. So I don’t know whether there is actually another RTC on the board.

Since the RTC is not very useful. I will let go hacking this part until I find other clues.

Here is the output of the original firmware.

X1205: I2C based RTC driver.
i2c-core.o: driver X1205 registered.
X1205: found X1205 on STR9100 I2C Adapter
ccr_write_enable: verify SR failed
i2c-core.o: client [X1205] registered to adapter [STR9100 I2C Adapter](pos. 0).
X1205: i2c_add_driver RTC driver.
X1205: misc_register RTC driver.

P990i Stylus Stuck

It had been several months since my Sony Ericsson P990 stylus got stuck inside the casing. I was a little bit annoyed, since I can’t put a new stylus in it, but didn’t care too much because most of the time I just use my hand to select the menu, and use the keyboard to enter text.

When I bought a Torx T6 screw driver to replace MacBook Pro’s hard drive, I realized that the same screwdriver can be used to open P990i casing. So, I opened the casing, and I can pull out the old stylus. The stylus was stuck in a spring mechanism which I guess used to prevent the stylus from falling to easily.

You can look the disassembly pictures at
my photo album.

One thing that may not be clear from the instructions on the Internet is this: To open the part that covers the front camera: pull it upward (that is toward the upper side of the phone).

Changing MacBook Pro Harddrive

Changing MacBook hard drive was very easy, and I thought that changing a MacBook Pro hard disk will also be easy. It turns out that I had to deal with 27 screws, some of them are Philips-head screw type, and some others are Torx screw type. Thankfully the guys at iFixit has made a wonderful tutorial.

I didn’t have a Torx T6 screwdriver, so I had to buy one. Unfortunately, I can’t find a single screwdriver for Torx T6, so I have to buy a set, which cost me 120 baht (about 3.5 USD). The process was relatively easy and takes about 30 or 40 minutes. If you don’t have the time or patience to do it, just remember that next time you want to upgrade your MacBook Pro hard drive, you should take it to the store (especially if your MacBook Pro is still under warranty).

As a tip: I use my digital camera to take pictures of every step, In case I forgot what is the previous state of the things I take apart.

Here are the photos that I took when replacing the hard drive: http://www.flickr.com/photos/yohanes/sets/72157619774176803/

LED driver

I was very tired lately because I have to do many other things beside hacking the agestar kernel. So when I have time this morning, I decided to work on the easiest part on my list: LED driver. Agestar NCB3AST only have one controllable led, inside the casing, so I don’t know how useful this is (I think you can peek a little bit when the casing is closed). The LED and LCD display front is actually controlled by different unit, not controllable by CPU. Because this part is not important, I decided to upload the patch later.

Right now I am starting to look at the RTC driver. Hopefully this one will be more useful.

Network Driver Problem Solved

I ported STAR 9100 network driver without a documentation, I just blindly use the old driver and modify it to fit with all of the changes in the networking stuff since kernel 2.4.27. The driver claims to support scatter/gather I/O, but there is no implementation of scatter gather I/O in the hard_start_xmit function. I don’t know whether this device supports it or not, so I just change this line:

dev->features |= NETIF_F_SG|NETIF_F_IP_CSUM

to this:

dev->features |= NETIF_F_IP_CSUM

http://tinyhack.com/agestar/patch-2.6.25.4-for-agestar-20080622.bz2

And now the sendfile function works (although it would be faster if the driver supports scatter/gather IO).