Logic Sniffer Stuff
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|1. Logic Sniffer Background
The Open Logic Sniffer is a tiny logic analyzer that is very small,
very portable, very useful, and for those inclined easy to
customize. The design is compatible with the SUMP Logic Analyzer,
and was created by the labs of Dangerous
Prototypes and the Gadget
Factory. The OLS plugs into a USB port on your
a program such as Jawi's OLS Client
The OLS uses a Xilinx FPGA for the heavy lifting. The source code
for it is open source. Thus if you're familiar with Verilog
or the VHDL language, you can change it. Same goes for the
They've arranged for Seeed Studio
to build it. Get
A logic analyzer is only
useful if you can connect it to something. For that you'll
need wiring harnesses. Seeed Studio sells them for
They're made from ribbon cable, with permanently attached clips.
I prefer the wiring harnesses from Sparkfun Electronics here
however. Saleae Logic also sells them plus separate test
The clips are a somewhat pricey upgrade though. Sparkfun
also sells jumper wires
that should work fine.
The OLS comes as an
assembled bare circuit board. Not so great for longevity.
If you want a case, you'll need to buy one
or make one. I chose the latter.
I used the Ponoko
service, with an Inkscape SVG
It's derived from J.J.
Shortcut's design. I used 3mm thick clear acrylic
plastic. For a tight fit, you should install headers in the
UART, ICGP, & ROM-ISP locations. For the buttons, a dab of
glue stick holds the
square plastic cutouts in place.
FPGA with HP16500/16550 style triggers -
Download Latest Release
A new FPGA image with advanced triggers modeled on features of HP
16500/16550. Click picture for details.