/sig_gen

A simple cost-effective demo, test, training, board for an oscilloscope made from a Raspberry Pi Pico

Primary LanguageCBSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

Sig Gen V1.1

  1. Introduction
  2. Features
  3. Getting Started
  4. Licenses

1. Introduction

I recently purchased a modern, reasonably capable oscilloscope. While waiting for the new scope to arrive I decided that I needed a way to quickly and simply test its basic functionality. I looked at several scope manufacturers' demo/test boards and while they were appealing, they were also reasonably pricey (hundreds of dollars). After careful consideration, I decided to use that money for other things and create my own basic test board. My goals were to create an inexpensive (couple of $), expandable, and customizable system that would be usable by a wide audience. I called the project Sig Gen and decided to open source it. Just be aware that even though I named it Sig Gen, it is NOT a general purpose highly functional signal generator. That was not its intended purpose.

If you have questions, comments, ideas or if something is not working as expected feel free to open a new issue or start a discussion. If you wish, you may also reach out to me directly at pwproj24@gmail.com

2. Features

Sig Gen will generate the following signals:

  • 10/20 MHz 50% Duty Cycle Waveform
  • 100/200 KHz 50%, 25%, 10%, 5%, 1% Duty Cycle Waveforms
  • 1/2 KHz 50% Duty Cycle Waveform
  • 60/120 MHz 50% Duty Cycle Waveform
  • UART Waveform
  • Manchester Encoded Data Waveform
  • Low frequency PWM-DAC Analog Waveforms
    • 83.19/166.38 Hz Ramp
    • 166.66/333.32 Hz Sawtooth
    • 75.75/151.5 Hz Staircase
    • 390.62/781.24 Hz Sine
    • 195.31/390.62 Hz Full Wave Rectified Sine
    • 75.75/151.5 Hz Staircase with a normally distributed center segment
    • 75.75/151.5 Hz Staircase with a uniformly distributed center segment
    • 1.0-1000.0/2.0-2000.0 Hz Direct Digital Synthesis Sine
  • I2C Waveforms
  • SPI Waveforms

Note: The Italic notation indicates the operating frequency when the 2X overclocking option has been enabled. The end of the README includes a photo that illustrates the signals listed in the previous table.

3. Getting Started

This distribution includes a full manual and a single page quick start "cheat-sheet". They can be found in the docs folder.

4. Licenses

A significant portion of this project utilizes code from the Raspberry Pi Pico example library. As such its license file LICENSE_RP_PICO.TXT applies. For the portion of the code that I authored, LICENSE_PW.TXT applies.

This is an open-source project that is free of charge. Use this project in any way you like (as long as it complies to the permissive license files).


Sig Gen V1.1