Using a Bus Pirate as Logic Analyzer

Dangerous Prototypes Bus Pirate

Using an forked version of the Open Logic Sniffer (available here) you can setup a Bus Pirate to act a digital logic analyzer.  Not a substitute for a dedicated logic analyzer, but can do the trick if necessary.  Amazingly enough the client runs on Windows, Mac OS X, Linux, and Solaris.

There are a few things to remember when setting up the OLS software when using it with a Bus Pirate.  I am assuming you have installed the FTDI driver and hooked up the device via USB.  I also highly recommend a nice set of logic probes to use with the pin header.

1. First make sure the correct device is selected by following Capture > Device > OpenBench LogicSniffer.
2. Next, select Capture > Begin Capture.  This will lead to a pop-up window with three tabs.  Make the following adjustments under the “Connection” tab:
1. Connection Type:  Serial Port
2. Analyzer port:  
3. Port Speed:  115200 bps
4. Device type:  Bus Pirate OLS mode
3. Now select the “Acquisition” tab and make sure the following is set:
1. Number scheme: Default
2. Sampling clock: Internal
3. Sampling rate:  1.000 MHz
4. Channel groups:  Make sure ‘0’ has a tick mark.
5. Recording size: 4.00kB
4. If triggering is desired, select the “Triggers” tab.  Make the following changes:
1. Trigger Enabled:  Make sure it has a tick mark.
2. There is a “Mask” row of 32 tick marks.  Make sure the 2 least significant bits (bit 0 and bit 1) have a tick mark.  These are the two right-most checkboxes.
5. Make sure device under inspection is running. 
6. Last click the “Capture” button at the bottom of the pop-up window.
7. Viola!  You will be presented the following: