HD44780 Character LCD: problem with I2C and ST NUCLEO-F401RE

Hello,
for now I still have problems including pull up resistors (4.7K) between SDA and SCL and VCC, although the error is now slightly different (I2C Write BUSY instead of Time out).

Interrogating the getPinMode() function, the B7 and B6 pins are configured as Analog input,
but also changing pin state\mode through pinMode() function before calling connectI2C() does not change the negative result.

Do you have another value of pull up resistor to suggest?

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Uncaught InternalError: Timeout on I2C Write BUSY
at line 1 col 121
...|4,c|4,c,c,d,d,d|4,d|4,d,d]);

                          ^

in function "a" called from line 1 col 7
a(51,1),a(50,1),a(40,1),a(12,1),a(6,1),a­(1,1),{write:a,clear...

  ^

in function "HD44780" called from line 1 col 150
...c|4,c,c,d,d,d|4,d|4,d,d]);});

                          ^

in function "connectI2C" called from line 1 col 51
var lcd = require("HD44780").connectI2C(I2C1, 0x7E);

                                              ^

Uncaught Error: Field or method "print" does not already exist, and can't create it on undefined
at line 1 col 4
lcd.print("Hello World!");
^
=undefined