UART¶

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

MiraOS supports independent operation of multiple UARTs.

Defines¶

Name	Value	Description
`MIRA_IODEF_UART0`	{ miraint_uart_read, miraint_uart_write, 0 }
`MIRA_IODEF_UART1`	{ miraint_uart_read, miraint_uart_write, 1 }
`MIRA_IODEF_UART2`	{ miraint_uart_read, miraint_uart_write, 2 }
`MIRA_IODEF_UART(_ID)`	{ miraint_uart_read, miraint_uart_write, (_ID) }

Types¶

Name	Type	Description
`mira_uart_input_callback_t`	`int(* )(uint8_t c, void *storage)`

Enums¶

mira_uart_parity_t¶

Name	Value	Description
`MIRA_UART_PARITY_NONE`
`MIRA_UART_PARITY_EVEN`
`MIRA_UART_PARITY_ODD`

Structs¶

mira_uart_config_t¶

Type	Name	Description
`int32_t`	baudrate
`mira_gpio_pin_t`	tx_pin	Pin to use as TXD
`mira_gpio_pin_t`	rx_pin	Pin to use as RXD
`mira_uart_parity_t`	parity

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.

Parameters

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

Return

See the enum definition.

Value	Description
`MIRA_SUCCESS`	UART was successfully initialized.
`MIRA_UART_ERROR_INIT`	UART could not initialize.
`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

Parameter	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

See the enum definition.

Value	Description
`MIRA_SUCCESS`	The callback was successfully set.