NAME        NUCLEO-042  SENSORS board

USART       USART2      USART1
USART_TX    PA2         PA9
USART_RX    PA15        PA10
    I2C
SCL         PA9         PB6
SDA         PA10        PB7
    Multiplexer
~EN         PA3         PB12
ADDR0..3    PA4..7      PB0..2 (!!!)
    LEDS
LED0        PB3         PB10
LED1        ---         PB11
