Uwe Hermann | A slightly paranoid Debian developer

I'm happy to finally announce an open-source (GNU GPL), cross-platform (Linux, Mac OS X, FreeBSD, Windows, ...) logic analyzer software package myself and Bert Vermeulen have been working on for quite a long time now: sigrok (it groks your signals).

History

I originally started working on an open-source logic analyzer software named "flosslogic" in 2010, because I grew tired of almost all devices having a proprietary and Windows-only software, often with limited features, limited input/output file formats, limited usability, limited protocol decoder support, and so on. Thus, the goal was to write a portable, GPL'd, software that can talk to many different logic analyzers via modules/plugins, supports many input/output formats, and many different protocol decoders.

The advantage being, that every time we add a new driver for another logic analyzer it automatically supports all the input/output formats we already have, you can use all the protocol decoders we already wrote, etc. It also works the other way around: If someone writes a new protocol decoder or file format driver, it can automatically be used with any of the supported logic analyzers out of the box.

Turns out Bert Vermeulen had been working on a similar software for a while too (due to exactly the same reasons, crappy Windows software, etc.) so it was only logical that we joined forces and worked on this together. We kept Bert's name for the software package ("sigrok"), set up a SourceForge project, mailing lists, IRC channel, wiki, etc. and started working.

Overview, Features

You can get the lastest sigrok source code from our main git repository:

  $ git clone git://sigrok.git.sourceforge.net/gitroot/sigrok/sigrok

Here's a short overview of sigrok and its features as of today. The software consists of the following components:

• libsigrok, a shared library written in C, which contains the general infrastructure for handling logic analyzer data in a streaming fashion.
  
  It also contains the individual hardware drivers which add support for various logic analyzers. Currently supported hardware includes: Saleae Logic, CWAV USBee SX, Openbench Logic Sniffer (OLS), ZEROPLUS Logic Cube LAP-C, ASIX Sigma/Sigma2, ChronoVu LA8, and others. Many more devices are on our TODO list (and we already own them), it's just a matter of time to reverse engineer the USB protocols and implement a driver for them.

  Thanks ASIX for being open and helping with the ASIX Sigma driver, and many thanks to ChronoVu for being open as well and providing information about the ChronoVu LA8 protocol! Thanks to Håvard Espeland, Martin Stensgård, and Carl Henrik Lunde (who contributed the ASIX Sigma driver), Sven Peter and "Haxx Enterprises"/bushing (for contributing the ZEROPLUS Logic Cube LAP-C driver, ported from their zerominus tool). Also, thanks to Daniel Ribeiro and Renato Caldas who worked on the Link Instruments MSO-19 driver (still work in progress).

  Finally, libsigrok also contains the individual input/output file format drivers. Currently supported are: sigrok session (the default format, which contains all metadata), bits, hex, ASCII, binary, gnuplot, the OpenBench Logic Sniffer format, the ChronoVu LA8 format, Value Change Dump (VCD) viewable in gtkwave, and Comma-separated values (CSV).
  

• libsigrokdecode, a shared library written in C, which contains the protocol decoder infrastructure and the protocol decoders themselves, which are written in Python (>= 3.0).

  The list of currently supported protocol decoders includes:
  

    dcf77                DCF77 time protocol
    lpc                  Low-Pin-Count
    mx25lxx05d           Macronix MX25Lxx05D
    jtag_stm32           Joint Test Action Group / ST STM32
    i2s                  Integrated Interchip Sound
    spi                  Serial Peripheral Interface
    edid                 Extended display identification data
    pan1321              Panasonic PAN1321
    mlx90614             Melexis MLX90614
    jtag                 Joint Test Action Group
    rtc8564              Epson RTC-8564 JE/NB
    transitioncounter    Pin transition counter
    usb                  Universal Serial Bus
    i2cdemux             I2C demultiplexer
    i2c                  Inter-Integrated Circuit
    i2cfilter            I2C filter
    mxc6225xu            MEMSIC MXC6225XU
    uart                 Universal Asynchronous Receiver/Transmitter
  

  Many more decoders are on our TODO list, and we especially welcome contributed protocol decoders, of course! We intentionally chose Python as implementation language for the decoders, to make them as easy to write (and understand) as possible, even if that means that performance suffers a bit. Have a look at the SPI decoder for example, to get a feeling for the implementation.

  Protocol decoders can be stacked on top of each other, e.g. you can run the i2c decoder and pipe its output into the rtc8564 (Epson RTC-8564 JE/NB) decoder for further processing of the RTC-specific, higher-level protocol. We also plan to support more complex stacking and combining of decoders in various ways in the nearer future.

• sigrok-cli, is a command-line frontend, which uses both libsigrok and libsigrokdecode. It can acquire samples from logic analyzers and output them in various formats into files or to stdout, and/or run protocol decoders on the aquired data.

  Example: Data acquisition with 1MHz samplerate into a file.
  

   $ sigrok-cli -d chronovu-la8:samplerate=1mhz --time 1ms -o test.sr
  

  Example: Protocol decoding (JTAG).
  

   $ sigrok-cli -i test.sr -a jtag:tdi=5:tms=2:tck=3:tdo=7
   [...]
   jtag: "New state: EXIT1-IR"
   jtag: "IR TDI: 11111110, 8 bits"
   jtag: "IR TDO: 11110001, 8 bits"
   jtag: "New state: UPDATE-IR"
   jtag: "New state: RUN-TEST/IDLE"
   [...]
  

• sigrok-qt, a Qt-based GUI for sigrok, using both libsigrok and libsigrokdecode.

  This is intended to be a cross-platform GUI (runs fine and looks "native" on Linux, Windows, Mac OS X) supporting data acquisition and protocol decoding.

  NOTE: The Qt GUI is not yet usable! We're working on getting it out of alpha-stage for the next release.

• sigrok-gtk, a GTK+-based GUI for sigrok, using both libsigrok and libsigrokdecode (soon).
  
  This is a cross-platform GUI contributed by Gareth McMullin (thanks!), supporting data aqcuisition (and soon protocol decoding).

  NOTE: The GTK+ GUI is not yet fully usable (but it's more usable than sigrok-qt)! Consider it alpha-stage software for now.

We're happy to hear about other (maybe special-purpose) frontends you may want to write using libsigrok/libsigrokdecode as helper libs!

Firmware

Some logic analyzer devices require firmware to be uploaded before they can be used. As always, firmware is a bit of a pain, but here's what we currently do: For non-free firmware we provide instructions how to extract it from the vendor software or from USB dumps, if possible. For distributable firmware we have a git repo where you can get it (thanks ASIX for allowing us to distribute the ASIX Sigma/Sigma2 firmware files!).

  $ git clone git://sigrok.git.sourceforge.net/gitroot/sigrok/sigrok-firmwares

Finally, for all Cypress FX2 based logic analyzers we have an open-source (GNU GPL) firmware named fx2lafw, started by myself, but most work (and finishing the firmware) was then done by Joel Holdsworth, thanks! The support list includes Saleae Logic, CWAV USBee SX, CWAV USBee AX, Robomotic Minilogic/BugLogic3, Braintechnology USB-LPS, and many others. Get the code from the fw2lafw git repository:

  $ git clone git://sigrok.git.sourceforge.net/gitroot/sigrok/fx2lafw

Example dumps

We collect various captured logic analyzer signals / protocol dumps in the sigrok-dumps git repository:

  $ git clone git://sigrok.git.sourceforge.net/gitroot/sigrok/sigrok-dumps

They can be useful for testing the sigrok command-line application, the sigrok GUIs, or the protocol decoders.

We're happy to include further contributed example data in our repository, please send us .sr files of any interesting data/protocol you may come across (even if sigrok doesn't yet have a protocol decoder for that protocol). See the Example dumps wiki page for details.

Packages, distros, installers

I'm currently working on updated Debian packages for sigrok (will be apt-get install sigrok to get everything), and we're happy about further packaging efforts for other distros. We have preliminary Windows installer files (using NSIS), but the Windows code needs some more fixes and portability improvements before it's really usable. On Mac OS X you can use fink/Macports to install as usual, fancier .app installer files are being worked on.

Future

Apart from support for more logic analyzers, input/output formats, and protocol decoders, we have a number of other plans for the next few releases. This includes support for analog data, i.e. support for (USB) oscilloscopes, multimeters, spectrum analyzers, and such stuff. This will also require additional GUI support (which could take a while). Also, we want to improve/fix the Windows support, and test/port sigrok to other architectures we come across. Performance improvements for the protocol decoding as well as more features there are also planned.

Contact

Feel free to contact us on the sigrok-devel mailing list, or in the IRC channel #sigrok on Freenode. There's also an identi.ca group for sigrok. We're always happy about feedback, bug reports, suggestions for improving sigrok, and patches of course!

There a many, many, e-book reader devices available these days, and they're quickly becoming pretty affordable. The currently cheapest device in Germany (that I know of) is the TrekStor eBook Reader 3.0, model number EBR30-a, at 59.- Euros via Weltbild or Hugendubel.

The device has an 800x480 7" TFT (yep, no e-ink), 2100mAh battery, it can display PDFs, EPUB, and TXT files (and Adobe DRM crap, which I don't really care about), it has an accelerometer which allows for landscape/portrait switching, it can play MP3, OGG, WAV, and WMA audio files (headphone jack), it can display pictures (BMP, GIF, JPG, even PNG, though that's not mentioned in the vendor's specs), and it has 2GB internal storage for books/music/pictures. Uploading of (non-DRM) content is done by a simple file copy, it enumerates as a standard USB mass storage device with FAT filesystem. It's a relatively nice reader for the price, I've read a few PDFs (datasheets, presentations) on it in the subway/train while listening to music from the device and it's quite OK for my purposes. So much for the review part.

However, I didn't really buy it for reading books on it, I was more interested in taking it apart, of course ;-) My hope was that it would turn out to be a really cheap device running Linux/U-Boot which would be perfect for playing around with embedded Linux stuff. Unfortunately, I wasn't so lucky (it seems).

I've posted a few photos of the device and its hardware components on my flickr account and over at randomprojects.org, together with all the information I was able to find out so far. Here's a quick summary:

• Main CPU/SoC: FI E200 B6077BA 26P1
• RAM: MIRA P3S12D40ETP (512MBit / 64MByte DDR SDRAM, max. 200MHz)
• NAND flash: Samsung K9GAG08U0E (16GBit / 2GByte, x8, 3.3V)
• Battery management: KrossPower AXP199 A5004AB 36G
• RTC/clock/calender chip (I2C): H8563S
• Some accelerometer (to switch between landscape/portait mode), model unclear so far, maybe the chip labeled 605 132?

There are public datasheets for most of the hardware components (see randomprojects.org for links), but unfortunately the most important one (for the CPU) is not yet found/identified. I was told that the CPU/SoC is probably based on an ARM9 (ARM926EJ-S) core and the firmware running on it seems to be some uCos-based RTOS (not Linux, unfortunately).

So far I was not able to find out the vendor name or website of the "FI E200" CPU/SoC (let alone any datasheets), any hints would be highly appreciated. I checked arm.com: Processor Licensees, but the only two companies whose name starts with "F" having licensed an ARM9 core are Fujitsu and Freescale, which doesn't fit, I think?

I could (and probably will) check the PCB for RX/TX lines on an UART and/or JTAG pads (none are obviously labelled), and given that it's and ARM9 core there is a good chance that OpenOCD can be used and that a standard cross-gcc toolchain for ARM will work. However, that is all pretty pointless until it's clear which SoC exactly is used, and thus whether there is already Linux and/or U-Boot support for it and/or whether datasheets are available so that the respective code could be written. Without datasheets, this is going to be a pretty painful experience, not really worth investing much time, IMHO.

If anyone knows more about the vendor/device and respective datasheets, please let me know. Thanks!

Update 2012-04-19: I found the UART TX pin a while ago, a bootlog is available. The CPU and all other chips are also known now: The SoC is an Allwinner Technology F1 E200, the orientation sensor is a MEMSIC MXC6225XU.