Feather M0 Sine Wave generator using ZeroDMA #Adafruit #Feather #ZeroDMA @MicrochipMakes

Feather M0 Sine Wave generator using ZeroDMA

Work by Adafruit forum members MartinL2 and BDL has provided great work on generating variable frequency sine waves on the digital to analog converter (DAC) on Adafruit Feather M0 (Microchip SAMD21 based) microcontroller boards.

I’m trying to make a (dynamic) swept sine generator to test an analog filter response. I’d like to stop DMA, load in a new frequency table, and restart DMA using the new (updated) table. Initially I’ll use + and – from the console to control the frequency, but later I will make a linear sweep.

SineWaveDMAC.jpg

Following up on this thread. I have modified MartinL2’s code to perform either a chirp or or a swept sine wave with “constant power” per frequency. The former is easier to see on a scope, but does not have constant power per frequency. This is true because each frequency (single cycle of a sine wave) is shorter and shorter as the frequency increases. If one observes this on an FFT, one sees the power per bin decreases as the frequency increases. The constant power mode emits a frequency for a unit time before changing. In this way the power as observed by an FFT should be constant. This mode is useful for characterizing filter frequency responses.

SDS00002.png

See this Adafruit Forums post for the details and the source code as it was developed. Great work!

Also, check out the Adafruit ZeroDMA Library in the Arduino IDE for all you can do.

And, check out the large number of SAMD21 (M0) based boards available from Adafruit.


Halloween season is here!
Halloween season is here! Check out all the posts, gift guides, and more!

Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards

Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.

Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7:30pm ET! To join, head over to YouTube and check out the show’s live chat and our Discord!

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Join over 38,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

CircuitPython – The easiest way to program microcontrollers – CircuitPython.org


New Products – Adafruit Industries – Makers, hackers, artists, designers and engineers! — New Products 10/30/24 Adafruit LPS28 (LPS28DFW) Pressure Sensor – STEMMA QT / Qwiic

Python for Microcontrollers – Adafruit Daily — Python on Microcontrollers Newsletter: New Raspberry Pi Products, 503 CircuitPython Libraries and Much More! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi

EYE on NPI – Adafruit Daily — EYE on NPI Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey

Adafruit IoT Monthly — Halloween, WiLo, and more!

Maker Business – Adafruit Daily — First Solar’s $1.1 billion development of vertically integrated factory in the U.S.

Electronics – Adafruit Daily — Trigger happy oscilloscope?

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !



No Comments

No comments yet.

Sorry, the comment form is closed at this time.