UART API

API Functionality

The API for UART functionality has the following functions available:

/* UART driver initialization function (without compile-time parameter checking) */
uhal_status_t uhal_uart_init(const uart_peripheral_inst_t uart_peripheral, 
                             const uint32_t baudrate, 
                             const uart_clock_sources_t clock_source, 
                             const uint32_t clock_source_freq, 
                             const uart_extra_config_opt_t uart_extra_opt);

/* UART driver transmit function (without compile-time parameter checking) */
uhal_status_t uhal_uart_transmit(const uart_peripheral_inst_t uart_peripheral, 
                                 const uint8_t* transmit_buffer, 
                                 const size_t size);

/* UART driver receive function (without compile-time parameter checking) */
uhal_status_t uart_receive(const uart_peripheral_inst_t uart_peripheral, 
                           uint8_t* receive_buffer, 
                           const size_t size);

/* UART driver deinit function */
uhal_status_t uhal_uart_deinit(const uart_peripheral_inst_t uart_peripheral);

uart_init function

uhal_status_t uhal_uart_init(const uart_peripheral_inst_t uart_peripheral, 
                             const uint32_t baudrate, 
                             const uart_clock_sources_t clock_source, 
                             const uint32_t clock_source_freq, 
                             const uart_extra_config_opt_t uart_extra_opt);

Description:

The uart_init function is designed for initializing a UART peripheral. It configures the peripheral with specific settings, including the clock source and additional options that dictate the behavior of the UART bus.

Parameters:

1. uart_peripheral (const uart_peripheral_inst_t):

   • Specifies the UART peripheral instance to initialize.

2. baudrate (const uint32_t):

   • Specifies the baudrate of the to be intiliazed UART connection.

3. clock_source (const uint32_t):

   • Determines the clock source for the UART peripheral. This setting is critical as it affects the timing and synchronization of UART communications.

4. uart_extra_opt (const uart_extra_config_opt_t):

   • Provides additional configuration options for the UART bus. These options can include settings for clock polarity, phase, data order, character size, and pad-specific configurations necessary for the correct operation of the UART slave peripheral.

Return:

• uhal_status_t: This function returns a status code that indicates whether the initialization was successful. It provides feedback on the setup process, helping to identify any issues that might have occurred during the initialization.

Working:

1. The initialization process begins with the assignment of the specified uart_peripheral to the desired UART peripheral. This step ensures that the correct hardware unit is being configured.

2. The clock_source is then configured, setting up the timing and synchronization aspect of the UART communication based on the microcontroller's clock system.

3. Additional configurations, as specified by uart_extra_config_opt, are applied. These settings enable the customization of the UART operation according to the specific requirements of the application, such as adjusting clock polarity, data order, and other bus-specific parameters.

4. The UART peripheral is then enabled, ready to participate in UART communications

uart_transmit function

uhal_status_t uhal_uart_transmit(const uart_peripheral_inst_t uart_peripheral, 
                                 const uint8_t* transmit_buffer, 
                                 const size_t size);

Description:

The uart_transmit function is used to transmit bytes over the serial bus.

Parameters:

1. uart_peripheral (const UART_host_inst_t): Specifies the UART peripheral instance to use for transmitting the bytes.

2. transmit_buffer (const uint8_t*): Specifies the buffer which contains the data to transmit

3. size (const size_t): Specifies the amount of bytes to transmit

Return:

• uhal_status_t: The function returns a status, giving an indication of whether the transmit was succesful or not.

uart_receive function

uhal_status_t uhal_uart_receive(const uart_peripheral_inst_t uart_peripheral, 
                                uint8_t* receive_buffer, 
                                const size_t size);

Description:

The uart_receive function is used to receive bytes over the serial bus.

Parameters:

1. uart_peripheral (const UART_host_inst_t): Specifies the UART peripheral instance to use for receiving the bytes.

2. receive_buffer (const uint8_t*): Specifies the buffer where the data has to be saved to

3. size (const size_t): Specifies the amount of bytes to receive

Return:

• uhal_status_t: The function returns a status, giving an indication of whether the receive was succesful or not.