stm32/boards/NUCLEO_F091RC: Enable with default pins.
#define MICROPY_HW_UART1_RX (pin_B7)
#define MICROPY_HW_UART2_TX (pin_A2)
#define MICROPY_HW_UART2_RX (pin_A3)
+#define MICROPY_HW_UART3_TX (pin_C10)
+#define MICROPY_HW_UART3_RX (pin_C11)
+#define MICROPY_HW_UART4_TX (pin_A0)
+#define MICROPY_HW_UART4_RX (pin_A1)
+#define MICROPY_HW_UART5_TX (pin_B3)
+#define MICROPY_HW_UART5_RX (pin_B4)
+#define MICROPY_HW_UART6_TX (pin_C0)
+#define MICROPY_HW_UART6_RX (pin_C1)
+#define MICROPY_HW_UART7_TX (pin_C6)
+#define MICROPY_HW_UART7_RX (pin_C7)
+#define MICROPY_HW_UART8_TX (pin_C2)
+#define MICROPY_HW_UART8_RX (pin_C3)
// USART2 is connected to the ST-LINK USB VCP
#define MICROPY_HW_UART_REPL PYB_UART_2
