Hello, I'm using a Arduino Due,

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(Jim Wittnebel) #1

Hello, I’m using a Arduino Due, and trying to run 6 strips of lights in a parallel-output configuration.

I also have an adafruit music maker shield hooked up to this. That is using most of the pins defined in Ports A, C, and D.

Is there a reason why it has to be these sets of pins? Can I redefine these? if so where would I redefine them?

(Yves BAZIN) #2

@Jim_Wittnebel to have a fast enough speed to write values to the pins the library uses direct port access. the pins of the arduino are split into ‘blocks’ A,B,C,D hence it exist low level command to set the values of the pin of a block really fast. Unfortunately these pins are not modifiable. to be able to choose the pins for the parallel output you would have to rewrite part of the code.
it could be done be will require some work.

(Jim Wittnebel) #3

Thanks for the quick response.

For PortD, they show pin 11 as the last pin, which is also part of the SPI port. If I don’t use that pin , will it still mess up the SPI port communications to the music maker?

Also, for the Due, only Port D has all the pins, It appears that the Due only has 53 digital pins. Or am I missing something somewhere?

(Yves BAZIN) #4

@Jim_Wittnebel if you don’t use that pin it should be ok
indeed it seems strange but if you look at the pinout of the Arduino due the digital pins are label differently but even then I did not find pin with number above 80

(Jim Wittnebel) #5

Nod, thanks. I agree, if someone looks to address this, it would be nice if we could setup a bank of pins to include a set that would include pins not part of a standard shield.

(Daniel Garcia) #6

The port/pin layout of the due borders on idiotic :slight_smile: — there’s another board that was getting made for a couple years that basically added a whole bunch more pins to the due layout, but I don’t think it gets made anymore. Unfortunately, the ports and pins correspond to physical pins on the underlying MCU - there really isn’t any remapping here that can be done without making your own version of the board and laying out the traces differently.