Mon, 25 Mar 2013
Linux on GK802
So far I've managed to port u-boot, and together with the squad in #imx6-dongle on Freenode IRC, the kernel is looking very healthy too. For more information, check out the project's github page. Support for getting started can be found on IRC.
Tue, 04 Sep 2012
Drag'n'Derp gets its own site
Sun, 08 Jul 2012
xfv-4-intel: an Intel .BIO extractor
Anyway, I found Christoph Pfisterer's xfv tool, which unpacks EFI firmware volumes and capsules. It was missing a couple of features I needed, like decompression of Intel's "custom" compression mode (actually LZMA), so here is a version suitable for dumping Intel BIOS files:
Sun, 01 Apr 2012
Drag'n'Derp: coming soon to an internet near you!
Tue, 08 Nov 2011
Resetting middle-aged Volvo service lights
Here's how to do it with an ELM327 or compatible OBD-II interface. You will need a terminal emulator such as minicom (Mac/Linux) or HyperTerminal (Windows). Hit enter after each command. Connect to the port, turn your ignition to II, and make sure linefeeds are on:
> AT L1Now set up your address as 0x13:
> AT RA 13And since you are talking to the instrument cluster (0x51), set the message header and target address:
> AT SH 83 51 15
> AT IIA 51You can now wake up the cluster controller:
> AT SIYou should see
BUS INIT...OKIf so, issue the reset command:
> B0 30If you're not sure it's communicating properly, you can try a gauge test - all the needles are moved to full scale and back:
> B0 31You can reissue
AT SIto restart communication at any time. Make sure you issue the reset within a couple of seconds of ATSI finishing, as the controller seems to go back to sleep pretty quickly. I'd be interested to hear from anyone who knows how to extract the odometer data from one of these - I've had no luck with commands A5, A7 or B9 (read data by offset/address, or read data block).
posted at: 02:24 | path: /reversing/volvo | permanent link to this entry
Mon, 26 Sep 2011
Motorola Atrix: Ubuntu Webtop Construction Kit
I have built a chroot filesystem based on NVIDIA's last Linux for Tegra release. Unfortunately, LfT has two serious incompatibilities with Android: Xorg hangs, and most binaries (including ls and mount) segfault on startup. The former problem is fairly simple to solve - Xorg hangs after submitting a command buffer to the rendering manager, so it looks like the channel mutex system is incompatible between the Android and Xorg libraries. Cribbing the relevant libraries from the original Webtop filesystem fixes that. Crashing binaries is more puzzling. It turns out that recent Android kernels for Tegra (including that used in the CM7 beta) include a hardware bug workaround that needs corresponding workaround in userspace/libc, or else it crashes. This is worked around by downgrading libc to version 2.12.1, which is not affected. The issue is described in more detail here.
This tarball includes a complete root filesystem. It has no dependency on the original webtop files; you can install it to /osh, or to an SD card partition. It's pretty small (under 200MB), and you'll need to set up your own X environment. A 'go' script is included to mount the needful and chroot from an Android root shell. An advantage of the updated Tegra driver is that you no longer need a crufty binary to change res - use xrandr instead. You will need to issue
xrandr --display DSI-1 --offto turn off the overlay on the phone screen when X starts up, though. This is not intended for end users. It is intended to help developers interested in building their own webtop replacements. It does not include the "android-in-window" binaries from the original webtop - all the headers you need are in /usr/include, so feel free to write your own! I'm not liable if it eats your cornflakes or puts gaffer tape on your cat, but here it is:
natty-base.tar.gz - 73MB
Update 26/9/11: I built eglibc 2.13 with
-mtp=softto work around the issue. Binaries here, updated tarball is base+glibc.tar.gz - 73MB.
posted at: 12:14 | path: /linux/atrix | permanent link to this entry
Sat, 30 Jul 2011
I'm Not Dead
Wed, 11 May 2011
Drag and Drop?
posted at: 12:55 | path: /gameboy | permanent link to this entry
Mon, 09 May 2011
Cart Sneak Peek
What is it? I'm building a new Gameboy cartridge. Not GBA, not DS, original Gameboy. Why? Because a lot of people still use them, in particular for creating music with software like Johan Kotlinski's LSDj. And to do this, you need a flashable cartridge.
Why? Currently available carts need custom drivers to talk to a computer, and for many types, a cart reader device. This limits their compatibility, and the drivers tend to be poorly maintained after release, too.
Another issue is that all current carts use battery-backed RAM to save user data to - read: music that artists have spent many hours on. These batteries can last ten years in a well-designed system - from the date of manufacture, putting a lifespan on the cartridge and leading to scary reliability issues as they age.
So some prototypes are up, and being tested; this cart is real, and it is coming.
posted at: 03:42 | path: /gameboy | permanent link to this entry
Thu, 07 Apr 2011
ShairPort 0.05 released
So, here is ShairPort, an open-source (Perl/C) replacement.
Fri, 04 Mar 2011
WM8505 state of play - March 2011
Hardware noteA number of WM8505 netbooks have a hardware bug where the sense line of the MMC/SD slot's write protect switch is reversed. These will sense unprotected SD cards as protected and vice versa. You will not be able to live-boot Bento Linux from a write-protected SD; it will hang when trying to mount the root filesystem, and consequently not load the framebuffer driver, and nothing will appear to happen.
Bento LinuxBento was released with a kernel stolen from an Android device, as that was the only way to get Linux running initially on the 8505 devices. Now that the source has been released, we can change the shortcomings of this kernel, namely compiling in framebuffer console, and removing the Android security model code. Nobody has done this yet (and rereleased the bento fatpart).
VIA's source releaseVIA released some source code for these tablets. A slightly cleaned-up version of the VIA tree has been published by Angus Gratton here. This needs configuring to work properly. Key variable for video is GE_BUFFER_SIZE or similar. A working config is available here (for netbook).
Open source reimplementationA completely open-source effort is underway to get a WM850x port into Linux mainline. This port is spearheaded by Alexey Charkov; its base is here. At this point, in addition to basic booting and serial, it supports video, RTC, keyboard. Tony Prisk has been working on MMC/SD patches, and there are also Ethernet support patches on the mailing list.
Development discussion takes place on a mailing list (here) - this group is for development discussion, not help requests, please!
HelpThe most active place for general help seems to be
posted at: 15:19 | path: /linux/wm8505 | permanent link to this entry
Sat, 29 Nov 1969
posted at: 14:00 | path: | permanent link to this entry