Logic Analyzer Built with KiCad: A Comprehensive Guide

“A low-cost 24-channel logic analyzer with fully open-source hardware and software, featuring 100Msps, 32k depth sampling, edge triggering, and pattern triggering. The project is continuously updated.”

Overview

The LogicAnalyzer is a low-cost analyzer based on the Raspberry Pico. This analyzer provides up to 24 digital channels, pre-trigger and post-trigger sampling, edge triggering, and pattern triggering, with a maximum of 16 bits.

The most basic version is a pure Pico prototype, which can be used simply by shorting GPIO0 and GPIO1 and uploading firmware. However, there are some limitations, as the Pico only supports 3.3 volts. If you want to use it to diagnose 5-volt signals, I have also designed a fast level shifter circuit board.

In addition to the hardware, the logic analyzer also includes powerful software (currently only supports Windows) where you can visualize the captured data, export the captured data, use protocol analyzers, etc.

Basic Parameters

In the first line of the dialog box, we can see the basic parameters of the acquisition: frequency (samples per second), pre-trigger sample count, and post-trigger sample count.

The frequency selector allows us to choose the number of samples collected per second, ranging from 3100 (3.1KHz) to 100000000 (100MHz).

Next is the number of samples stored before triggering, which is very useful for verifying the channel states prior to meeting the trigger conditions.

Finally, the number of samples stored after triggering, which will be our main captured data.

The number of samples we can capture depends on how many channels and which channels we have captured. The limits are:

• Up to 8 channels (Mode 0)
• At least 2 pre-trigger sample points
• Up to 98303 pre-trigger samples
• At least 512 post-trigger sample points
• Up to 131069 post-trigger samples
• Up to 16 channels (Mode 1)
• At least 2 pre-trigger sample points
• Up to 49151 pre-trigger samples
• At least 512 post-trigger sample points
• Up to 65533 post-trigger samples
• Up to 24 channels (Mode 2)

• At least 2 pre-trigger sample points
• Up to 24576 pre-trigger samples
• At least 512 post-trigger sample points
• Up to 32765 post-trigger samples

Schematic & PCB

Logic Analyzer:

Level Shifter:

License

GPL 3.0

Repository & Downloads

The open-source repository can be found on GitHub:

https://github.com/gusmanb/logicanalyzer

Baidu Download: