pour avoir le Module Wifi sur le serial il faut être sur le serial 6.
/**
* Select a secondary serial port on the board to use for communication with the host.
* This allows the connection of wireless adapters (for instance) to non-default port pins.
* Serial port -1 is the USB emulated serial port, if available.
*
* :[-1, 0, 1, 2, 3, 4, 5, 6, 7]
*/
#define SERIAL_PORT_2 6