problems adding support for Nucleo-L4P5

[PerennialNovice]

Hi,
I try to add support for Nucleo-L4P5 and started off adding a generic variant following all the steps described in the wiki article.
I finally tried to execute the CheckVariant sketch sketch but could not get serial output.
To rule out any of my setup other than the board itself, I tried the CheckVariant sketch on Nucleo-L4R5 which (after some trouble #1517) worked out fine (using SWD download for some reason unknown to me needs a manual reset).
When I select Generic-L4R5 however, no serial output was generated.
I then copied the clock setup from Nucleo to the generic variant but this did not change anything (the new clock setup gets used - I check by inserting a #pragma message to the function).

Seems that there is more to the Nucleo-implemantation that needs to be done to have the generic variant work...

What am I missing?
Very happy for every hint and answer!

[fpistm]

When I select Generic-L4R5 however, no serial output was generated.

If you use the generic with the Nucleo then you have to redefine the default Serial pin.
As default Serial for Nucleo L4R5 are:

Arduino_Core_STM32/variants/STM32L4xx/L4R5Z(G-I)T_L4R7ZIT_L4S5ZIT_L4S7ZIT/variant_NUCLEO_L4R5ZI.h

Lines 218 to 229 in 6479b8a

	#ifndef SERIAL_UART_INSTANCE
	#define SERIAL_UART_INSTANCE 101 //Connected to ST-Link - LPUART1
	#endif
	// Serial pin used for console (ex: stlink)
	// Required by Firmata
	#ifndef PIN_SERIAL_RX
	#define PIN_SERIAL_RX PG8
	#endif
	#ifndef PIN_SERIAL_TX
	#define PIN_SERIAL_TX PG7
	#endif

While generic define them as:

Arduino_Core_STM32/variants/STM32L4xx/L4R5Z(G-I)T_L4R7ZIT_L4S5ZIT_L4S7ZIT/variant_generic.h

Lines 229 to 240 in 6479b8a

	#ifndef SERIAL_UART_INSTANCE
	#define SERIAL_UART_INSTANCE 4
	#endif
	// Default pin used for generic 'Serial' instance
	// Mandatory for Firmata
	#ifndef PIN_SERIAL_RX
	#define PIN_SERIAL_RX PA1
	#endif
	#ifndef PIN_SERIAL_TX
	#define PIN_SERIAL_TX PA0
	#endif

To change them you can use the setRx() and setTx() API before the begin() or connect a FTDI to the correct pins.

[PerennialNovice]

Thank you very much!

I feel a bit ashamed not having thought of the pins myself...