New note:

A [GPIO] pin [on a SAM E5x/D5x] may operate in an open-drain mode, but the way we set its value is different to the one we do it with a “classic” totem-pole (push-pull) output. More here: https://spiffyk.cz/notes/#sam-port-open-drain

#microchip #ATSAM #SAM #ARM #embedded #programming

At my day job I'm working on some #firmware for things built around the #Microchip #SAM D5x/E5x #ARM-based microcontroller. As I'm still pretty new to #embedded programming and we're doing this bare-metal—from the data sheet—I've started collecting some notes about things that surprised me while doing that. They're on my website. Perhaps someone besides me will find this useful. The list is also going to be growing as we go.

https://spiffyk.cz/notes/#sam

#atmel #atsam #cprogramming

First multi multiple SAD trigger worked for me, after 5 days work.

One important this is choosing reference, which won't be same accross not just MCUs, but also compilers.

Adding hover over the stupid bokeh graphs will make it lot clearer where to start with your reference:

So if your figure variable is `o` like this, add the HoverTool part:

o = figure(plot_width=1200)

o.add_tools(HoverTool(show_arrow=False, line_policy='next', tooltips=[
('X_value', '@x'),
('Y_value', '@y')
]))

Now since we are using the most negative point for a round of AES, choose that X as reference (from first pic), maybe minus 2 or so:

reference = trace.wave[12715:20000] #ATSAM
scope.SAD.reference = reference

You might change the adc.segments based on where you started it, from 11 in the example to 10 or 9.
Only then will multiple SAD work (see second pic)

Mein braver Teststick :-) ... 2 x #CANFD, 1 x #LIN, 1 x #USB (serial) und ein paar digitale, analoge und comms auf Stiftleisten rausgeführt. Schnell zusammengenagelt in dieses schöne kleine USB-Stick-Gehäuse, damit die Sammy-C21-Platine mit dem LIN-Transceiver sicher verpackt ist.

Für die Feldbusse nehm ich dann diverse D-Sub auf Dupont-Adapter nach Bedarf. Ein sehr nützliches Ensemble.

#Elektronik #ATSAM #C21 #Atmel #Microchip #CAN #USB #maker