Demo of my #microcontroller #SeeedXIAO
#samd21 based #synthesizer processed with #eurorackmodular

https://youtu.be/sbO1S4QR78Q

Put my #SeeedXIAO #samd21 #diy #synthesizer in a temporary case made from a random cardboard box, to further work on its firmware.

I now have bunch of tiny #SAMD21 and #RP2040 dev boards.
In the picture you can see (left to right, top to bottom) an Adafruit QT-Py RP2040, a Waveshare RP2040-Zero, a Seeed Studio XIAO SAMD21 and an Adafruit QT-Py SAMD21.
I also plan on obtaining an Seeed Studio XIAO RP2040 for completeness sake.

The new tool chain is based on Great Scott Gadgets' apollo.
https://github.com/greatscottgadgets/apollo

I did initial test with mkj's QT-Py port
https://github.com/mkj/apollo/tree/qtpymerge

But due to the chip shortage, #SAMD21 also weren't available for quite a while.
This gave me a good excuse to get more familiar with TinyUSB and resulted in an #RP2040 port of apollo.
https://github.com/greatscottgadgets/apollo/pull/12

#niceplots #arduino #samd21

https://forums.adafruit.com/viewtopic.php?f=52&t=186355#p903215

So I devised a set-up to measure the internal 32 kHz crystal (OSC32K) characteristics, ie frequency and clock jitter. First I calibrated the clock of an audio recorder with a GPS time signal to find out it was sampling at EXACTLY 47998.519 Hz. I then recorded for almost an hour EACH one second tic the #SAMD21 produced (using the RTCZero #Arduino library).

Le graphique précédent est trompeur quand à l'évaluation du tressautement de l'horloge (clock jitter): il est basé sur l'horodatage des serial.println() dans l'IDE Arduino alors que le débit de l'interface série était réglée à 9600 bauds 🤦‍♂️ La précision affichée à la milliseconde près est factice... #samd21

Most Thoroughly Commented #Linker Script in The World: Arm #SAMD21

https://github.com/theacodes/Winterbloom_Castor_and_Pollux/blob/master/firmware/scripts/samd21g18a.ld

Oyez, oyez: un nouvel ajout au journal de bord de mon projet #audiosync #video #arduino #samd21 #gps

https://hackaday.io/project/176196-atomic-synchronator/log/187600-turning-on-the-soldering-iron