How to use the serial communication for debugging


I wanted to know how to use the serial port to debug grovepi activity directly from the raspbery pi
like [Firmware/Source/grovepi/src/grovepi_refactored.ino].

I want to send debug info using

Serial.print("[Debug]: Hello");
From GrovePi, and read it on the Rpi serial port (/dev/ttyama0)

GrovePi is providing two serial ports (RPISER, SERIAL) cf

  • RPISER seem to be connected directly to RPI serial port (but not to ATMEGA chipset)
  • SERIAL seem to be connected to the GrovePi ATMEGA chipset (but not to Rpi)

Is-it correct ?

Note: On the Raspberry pi 3 there is a port conflict usage with Bluetooth & serial, that i solved ( sudo raspi-config Select Interfacing Options / Serial …disable console…; use enable_uart=1 and pi3-disable-btmodule in /boot/config.txt; remove the word phaseconsole=ttyAMA0,115200 in /boot/cmdline.txt)

Now, do i need to connect the SERIAL to RPISER (TX<->RX) to retrieve serial debug info (how to do it to not destroy it) ?