MKR Motor Carrier LED: what does it mean?

[apagliari]

Maybe I'm missing something, but I wasn't able to find the documentation related to this led:

Does anyone have a clue about this led and its meaning? And maybe the related documentation?

Thanks in advance for any specific help here.

Andrea

[J-M-L]

if I remember there are LEDs to indicate the direction of the rotation. Not sure if it's one of those (I think they would be closer to the screw terminals)

EDIT: looking at the documentation, it's not one of those

[J-M-L]

so I did a bit of digging looking at the documentation and the schematic and trying to identify all LEDs

By elimination it seems that the LED highlighted in purple in my drawing is LED_S

which would be connected to pin PA03 of the underlying board.

and this is confirmed if you go look in the library you'll see

#define LED_BUILTIN   3

this seems coherent as you can see that the IN1 and IN2 pins of Motor 1 and 2 are connected to PA04 ... PA07 and in the same file you see

#define MOTOR_2_PIN_A     4
#define MOTOR_2_PIN_B     5
#define MOTOR_1_PIN_A     7
#define MOTOR_1_PIN_B     6

So it appears to be a LED that can be controlled by the firmware

in the file D11-Firmware.ino you can see this pin is made an OUTPUT which would pull it LOW and the way this LED is wired means that would turn on the LED.

But that being said, I've no clue what this D11-Firmware is

[apagliari]

Hi J-M-L,

thanks a lot for the deep dive into the schematics and for the reverse engineering of the documentation!

I'm wondering if someone from the Arduino engineers that build this board could provide some direct explanation here.

Since the led is ON and the carrier is not working maybe it has a meaning... who knows?

[J-M-L]

I could not find another direct reference to the led in the code so if the firmware is what is on the board in some way then the led will always turn on

The arduino engineering team does not read the forum much so I doubt they will jump in. May be raising a question in GitHub would draw attention

[apagliari]

Hi J-M-L,
I didn't managed to get a proper answer, but if the ORANGE led (and not RED as reported in the documentation) in ON (and NOT 'blinking' as found in another document), it means that there is the need to update motor carrier firmware as following described:

https://support.arduino.cc/hc/en-us/articles/360012963760-How-to-update-the-MKR-Motor-Carrier-Firmware

Very humbled about how complex is to find aswers to very smple questions, but at least I was able to recover the situation.

Thanks again for your deep research here!

I'm closing the thread .

Andrea

[J-M-L]

Thanks for following up!