Many cute embedded nonsense hacks involve connecting newly developed
(und thus untested) modules through untested cabling to a
controller in the main system being driven only by a rudimentary
kernel driver still in development.
In such situations, it is very difficult to establish a good
starting point for bug hunting without being able to actually look at the
physical hardware signals. Of course we want to do this within
the realm of our well known Free Software tools, but more important is
the practical use of the complete setup.
This page is meant to collect knowledge about such working setups that
hopefully allow other people to save lots of time and research. Also note
that the information is completely independant from the hardware vendors unless
Tool independant software
project aims at creating a portable, cross-platform,
Free/Libre/Open-Source signal analysis software suite that supports various device types
(e.g. logic analyzers, oscilloscopes, and many more).
From the list below,
ASIX Sigma / ASIX Sigma 2
The vendor page can be found at ASIX Sigma
ASIX Sigma and ASIX Sigma 2 are supported by the Sigrok
software, thus can
be used in Linux to debug various busses. There are multiple pros speaking
- Low cost for good parameters:
The device can do sampling at these sample rates:
16 channels @ 50 MHz
8 channels @ 100 MHz
4 channels @ 200 MHz
Note that the official website site does list also lower sampling
rates than 50MHz, but this is achieved by dividing the 50MHz clock
generator to a suitable rate. Due to the RLE encoding of samples
in the internal memory of the device, the benefit of lower sample
rates is low.
- Documentation is available:
ASIX provided me with a complete documentation for the device,
thus I was able to repair the support for this device in Sigrok.
The documentation is under non-restrictive NDA and is written in
Czech, which is likely the only possible barrier here. ASIX is
very supportive when it comes to support of this device in open
- Support in open-source tools:
The support for the device is available in Sigrok and was repaired in
recent revisions of libsigrok . A Sigrok wiki entry can be found
All in all, ASIX Sigma 2 is a good pick if you need a logic analyzer. While the
software support in Sigrok still needs some polishing, it's getting there and I
believe we should support companies which try to help Open Source solutions even
if it's only by giving out the documentation on a per-request basis.
The successor of Sigma 2 , the Omega
is not supported by Sigrok yet.
Open Logic Sniffer
Bus analyzers / Bus specific tools
Totalphase Beagle SPI/I2C
This analyzer is connected via USB to the Host. The
company provides data analyzing software for Linux, too. There is even an API
to get the samples directly via own software.
Rather it is not open source and a library is delivered as binary. But
it is possible to get samples from a remotely attached analyzer.
The delivered software works well on Linux. One advantage of this
analyzer, at least in my case, is that the customer bought himself one
and we could simply share the trace data. The customer can still run on
Windows (we cannot constraint customers to switch on a working OS,
rather...), but I can analyze the produced data on my Linux PC.
Totalphase Beagle USB Analyzer
This is the Beagle adapter for the USB bus. The company offers several
analyzer for USB 12 for Full/Low speed up to new models for USB-3.
The USB 480 is in my opinion a good choice for embedded, because
most SOCs have HS controller. The same "Data Center Software" is delivered for all
analyzer, allowing to switch among the busses. It works flawlessly under Linux
(tested on Ubuntu 10.04/12.04
This is a CAN interface for PC. Drivers were merged into mainline,
for older kernel versions the site supplies kernel drivers.
It works fine with Linux can-utils (cansend, candump,..)
This is a quite old and now discontinued 2-channels, 100Mhz, portable oscilloscope. It can be connected
to PC via the old RS-232 interface and a special cable.
- thscopy.c: Get Hardcopy via RS-232 interface.
The DPS series is a PC controlled stabilized power supply. In the attachment, a small utility to remotely control
Note to future editors
Let's start with a single page for now so that
we can see the similarities of the entries more easily. When the structure
solidifies, we should then start to split out the individual tools.
- thscopy.c: Utility to get a hardcopy of THS-720A via RS-232 interface
- voltcraft.c: Utility to control Voltcraft DPS-4005