April 7, 2022

Logic Analyzers - Open Workbench Logic Sniffer

Mine is an Open Bench Logic Sniffer v1.04 This will capture 100 Msps on 16 channels. With a daughterboard, it can do 32 channels. (but I don't have the daughterboard).

Apparently it is no longer being made, which is too bad. I had better take care of mine. Price is/was $50 and you get a decent set of probes as part of the deal.

I find a mini-USB cable and plug it in. This is on a Fedora 35 system in 2022 mind you. Two LED come on and on my linux system I see: 

new full-speed USB device number 4 using ehci-pci
New USB device found, idVendor=04d8, idProduct=fc92, bcdDevice= 1.00
New USB device strings: Mfr=1, Product=2, SerialNumber=0
Product: Logic Sniffer CDC-232
Manufacturer: Microchip Technology Inc.
ttyACM0: USB ACM device
The old Sparkfun page has a lot of forum discussion, and it is common for people to want to update this to the latest firmware (and there is firmware for both the PIC and the FPGA). The transceiver (level shifter) tolerates up to 7 volts. There is a 216K block ram so you get 8 channels with 24K samples, or 16 channels with 12K samples. Somehow it can also do 32 channels with 8k samples. Apparently to get 32 channels, you need a "wing expansion header" that I don't have.

This was designed to be used with SUMP.

Latest firmware

The file you are looking for is: ols-0308-expert.tgz. I have looked pretty hard for it online and no luck yet.

Have any comments? Questions? Drop me a line!

Tom's Electronics pages / [email protected]