+void
+ao_serial1_putchar(char c)
+{
+ ao_usart_putchar(&ao_stm_usart1, c);
+}
+
+int
+ao_serial1_pollchar(void)
+{
+ return ao_usart_pollchar(&ao_stm_usart1);
+}
+
+void
+ao_serial1_set_speed(uint8_t speed)
+{
+ ao_usart_set_speed(&ao_stm_usart1, speed);
+}
+#endif /* HAS_SERIAL_1 */
+
+#if HAS_SERIAL_2
+
+struct ao_stm_usart ao_stm_usart2;
+
+void stm_usart2_isr(void) { ao_usart_isr(&ao_stm_usart2, USE_SERIAL_2_STDIN); }
+
+char
+ao_serial2_getchar(void)
+{
+ return ao_usart_getchar(&ao_stm_usart2);
+}
+
+void
+ao_serial2_putchar(char c)
+{
+ ao_usart_putchar(&ao_stm_usart2, c);
+}
+
+int
+ao_serial2_pollchar(void)
+{
+ return ao_usart_pollchar(&ao_stm_usart2);
+}
+
+void
+ao_serial2_set_speed(uint8_t speed)
+{
+ ao_usart_set_speed(&ao_stm_usart2, speed);
+}
+#endif /* HAS_SERIAL_2 */
+
+#if HAS_SERIAL_3
+
+struct ao_stm_usart ao_stm_usart3;
+
+void stm_usart3_isr(void) { ao_usart_isr(&ao_stm_usart3, USE_SERIAL_2_STDIN); }
+
+char
+ao_serial3_getchar(void)
+{
+ return ao_usart_getchar(&ao_stm_usart3);
+}
+
+void
+ao_serial3_putchar(char c)
+{
+ ao_usart_putchar(&ao_stm_usart3, c);
+}
+
+int
+ao_serial3_pollchar(void)
+{
+ return ao_usart_pollchar(&ao_stm_usart3);
+}
+
+void
+ao_serial3_set_speed(uint8_t speed)
+{
+ ao_usart_set_speed(&ao_stm_usart3, speed);
+}
+#endif /* HAS_SERIAL_3 */
+
+void
+ao_serial_init(void)
+{
+#if HAS_SERIAL_1
+ /*
+ * TX RX
+ * PA9 PA10
+ * PB6 PB7 *
+ */
+
+#if SERIAL_1_PA9_PA10
+ stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOAEN);
+
+ stm_afr_set(&stm_gpioa, 9, STM_AFR_AF7);
+ stm_afr_set(&stm_gpioa, 10, STM_AFR_AF7);
+#else
+#if SERIAL_1_PB6_PB7
+ stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOBEN);
+
+ stm_afr_set(&stm_gpiob, 6, STM_AFR_AF7);
+ stm_afr_set(&stm_gpiob, 7, STM_AFR_AF7);
+#else
+#error "No SERIAL_1 port configuration specified"
+#endif
+#endif
+ /* Enable USART */
+ stm_rcc.apb2enr |= (1 << STM_RCC_APB2ENR_USART1EN);
+
+ ao_stm_usart1.reg = &stm_usart1;
+ ao_usart_init(&ao_stm_usart1);
+
+ stm_nvic_set_enable(STM_ISR_USART1_POS);
+ stm_nvic_set_priority(STM_ISR_USART1_POS, 4);
+#if USE_SERIAL_1_STDIN
+ ao_add_stdio(ao_serial1_pollchar,
+ ao_serial1_putchar,
+ NULL);
+#endif
+#endif
+
+#if HAS_SERIAL_2
+ /*
+ * TX RX
+ * PA2 PA3
+ * PD5 PD6
+ */
+
+#if SERIAL_2_PA2_PA3
+ stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOAEN);
+
+ stm_afr_set(&stm_gpioa, 2, STM_AFR_AF7);
+ stm_afr_set(&stm_gpioa, 3, STM_AFR_AF7);
+#else
+#if SERIAL_2_PD5_PD6
+ stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIODEN);
+
+ stm_afr_set(&stm_gpiod, 5, STM_AFR_AF7);
+ stm_afr_set(&stm_gpiod, 6, STM_AFR_AF7);
+#else
+#error "No SERIAL_2 port configuration specified"
+#endif
+#endif
+ /* Enable USART */
+ stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_USART2EN);
+
+ ao_stm_usart2.reg = &stm_usart2;
+ ao_usart_init(&ao_stm_usart2);
+
+ stm_nvic_set_enable(STM_ISR_USART2_POS);
+ stm_nvic_set_priority(STM_ISR_USART2_POS, 4);
+#if USE_SERIAL_2_STDIN
+ ao_add_stdio(ao_serial2_pollchar,
+ ao_serial2_putchar,
+ NULL);
+#endif
+#endif
+
+#if HAS_SERIAL_3
+ /*
+ * TX RX
+ * PB10 PB11
+ * PC10 PC11
+ * PD8 PD9
+ */
+#if SERIAL_3_PB10_PB11
+ stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOBEN);
+
+ stm_afr_set(&stm_gpiob, 10, STM_AFR_AF7);
+ stm_afr_set(&stm_gpiob, 11, STM_AFR_AF7);
+#else
+#if SERIAL_3_PC10_PC11
+ stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOCEN);
+
+ stm_afr_set(&stm_gpioc, 10, STM_AFR_AF7);
+ stm_afr_set(&stm_gpioc, 11, STM_AFR_AF7);
+#else
+#if SERIAL_3_PD8_PD9
+ stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIODEN);
+
+ stm_afr_set(&stm_gpiod, 8, STM_AFR_AF7);
+ stm_afr_set(&stm_gpiod, 9, STM_AFR_AF7);
+#else
+#error "No SERIAL_3 port configuration specified"
+#endif
+#endif
+#endif
+ /* Enable USART */
+ stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_USART3EN);
+
+ ao_stm_usart3.reg = &stm_usart3;
+ ao_usart_init(&ao_stm_usart3);
+
+ stm_nvic_set_enable(STM_ISR_USART3_POS);
+ stm_nvic_set_priority(STM_ISR_USART3_POS, 4);
+#if USE_SERIAL_3_STDIN
+ ao_add_stdio(ao_serial3_pollchar,
+ ao_serial3_putchar,