UART¶

A universal asynchronous receiver-transmitter (UART) is a peripheral device for asynchronous serial communication.

The UART API supports one UART on all MCUs, except nRF52840 where UARTE1 (UART ID=1) also can be used, but only for output.

Defines¶

MIRA_IODEF_UART0¶

#define MIRA_IODEF_UART0

MIRA_IODEF_UART1¶

#define MIRA_IODEF_UART1

MIRA_IODEF_UART2¶

#define MIRA_IODEF_UART2

MIRA_IODEF_UART¶

#define MIRA_IODEF_UART(_ID)

Types¶

mira_uart_input_callback_t¶

typedef int(* mira_uart_input_callback_t) (uint8_t c, void *storage);

Enums¶

mira_uart_parity_t¶

Name	Description
`MIRA_UART_PARITY_NONE`
`MIRA_UART_PARITY_EVEN`
`MIRA_UART_PARITY_ODD`

Structs¶

mira_uart_config_t¶

Name	Type	Description
`baudrate`	`int32_t`
`tx_pin`	`mira_gpio_pin_t`	Pin to use as TXD
`rx_pin`	`mira_gpio_pin_t`	Pin to use as RXD
`parity`	`mira_uart_parity_t`	Please note: Parity is not yet supported

Functions¶

mira_uart_init¶

mira_status_t mira_uart_init(uint8_t uart_id, const mira_uart_config_t *config);

Initialize a UART module.

The custom config is passed as a parameter (NULL for platform default).

Note

This might start a higher resolution clock in the CPU, which can significantly increase the power consumption until CPU is restarted. UART 1 is only available on nRF52840 MCUs and only for TX.

Parameters¶

Name	Description
uart_id	The index of the UART peripheral.
config	Pointer to a configuration to setup.

Return value¶

Name	Description
MIRA_SUCCESS	UART was successfully initialized.
MIRA_UART_ERROR_INIT	UART could not initialize.
MIRA_ERROR_NOT_SUPPORTED	Invalid UART id.

mira_uart_deinit¶

mira_status_t mira_uart_deinit(uint8_t uart_id);

Deinitialize a UART module.

Parameters¶

Name	Description
uart_id	The index of the UART peripheral.

Return value¶

Name	Description
MIRA_SUCCESS	UART was successfully deinitialized.
MIRA_UART_ERROR_INIT	UART could not be deinitialized.
MIRA_ERROR_NOT_SUPPORTED	Invalid UART id.

mira_uart_set_input_callback¶

mira_status_t mira_uart_set_input_callback(uint8_t uart_id, mira_uart_input_callback_t cb, void *storage);

Set a callback to be called on UART byte input.

Parameters¶

Name	Description
uart_id	The index of the UART peripheral.
cb	The callback to call.
storage	Storage pointer which is used to store optional information to be used by the callback function. E.g. it could be used as an identifier or to pass on a configuration struct.

Return value¶

Name	Description
MIRA_SUCCESS	The callback was successfully set.
MIRA_ERROR_NOT_SUPPORTED	Invalid UART id.