Board to Board communication

[benedikt_schwar]

Hello,

I need two S32K144-Board to communicate with each other by toggling a PIN, so that the routine I need on both boards can be synchronized. This doesn't work like I want to and I guess reading the PIN doesn't work. 
I am using the PINs PTC14 (as input) and PTC3 (as output).

So as far as I know the code should just look like the following:

Board1:

            PTC->PSOR |= 1<<3;

Board2:

            if(PTC->PDIR & (1<<14)){

                  //do something

            }

Still this doesn't work like expected. PTC is high but PTC 14 doesn't recognize this. Do I need some kind of shared ground potential to get this working (-> how?) or am I getting something wrong with the implementation?

[benedikt_schwar]

Hello Daniel,

I am using the EVB but according to the QuickStart Guide (https://www.nxp.com/docs/en/quick-reference-guide/S32K144EVB-QSG.pdf ) page 5 it says J4-14 PTC14 is GPIO?
And when defining it as GPIO in the pin_mux:PinSettings it should work anyways in my opinon?

[danielmartynek]

Hello Benedikt,

Yes, the pin can be used as GPIO input.

But anyway, the PTC14 pin is connected to the potentiometer and PTC3 is connected to one of the touch pads.

So I would recommend using other pins.

Have you measured the voltage on the pin?

Thanks,

Daniel

[danielmartynek]

Hello,

Do you use EVBs or your own boards?

On the S32K144 EVB PTC14 is connected the on-board potentiometer.

BR,

Daniel

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