half-duplex UART Driver

This module contains drivers for UART half-duplex communication bus.

It needs to manage the communication direction by enabling or disabling TX.

enum @173
UART_HALF_DUPLEX_OK = UART_OK
everything in order
UART_HALF_DUPLEX_NODEV = UART_NODEV
invalid UART device given
UART_HALF_DUPLEX_NOBAUD = UART_NOBAUD
given baudrate is not applicable
UART_HALF_DUPLEX_INTERR = UART_INTERR
all other internal errors
UART_HALF_DUPLEX_NOMODE = UART_NOMODE
given mode is not applicable
UART_HALF_DUPLEX_NOBUFF = -5
invalid buffer given
int uart_half_duplex_init(uart_half_duplex_t * dev, uint8_t * buffer, msp430_types.h::size_t buffer_max_size, const uart_half_duplex_params_t * params)

Initialize the half-duplex UART bus to communicate with devices.

Parameters

dev:the device
buffer:the buffer used for TX and RX
buffer_max_size:
 the buffer size
params:the initialization parameters

Return values

  • UART_HALF_DUPLEX_OK if everything is in order
  • UART_HALF_DUPLEX_NODEV if invalid UART device was given
  • UART_HALF_DUPLEX_NOBAUD if given baudrate is not applicable
  • UART_HALF_DUPLEX_INTERR if an other internal error occured
  • UART_HALF_DUPLEX_NOMODE if the given mode is not applicable
  • UART_HALF_DUPLEX_NOBUFF if an invalid buffer was given
void uart_half_duplex_set_tx(uart_half_duplex_t * dev)

Set the half-duplex UART bus in TX mode.

Parameters

dev:the device

void uart_half_duplex_set_rx(uart_half_duplex_t * dev)

Set the half-duplex UART bus in RX mode.

Parameters

dev:the device

msp430_types.h::size_t uart_half_duplex_send(const uart_half_duplex_t * dev, msp430_types.h::size_t size)

Send the data contained in the driver’s buffer.

Parameters

dev:the device
size:the number of characters to send

Return values

  • the number of characters actually sent
msp430_types.h::size_t uart_half_duplex_recv(const uart_half_duplex_t * dev, msp430_types.h::size_t size)

Recv data an fill the driver’s buffer.

Parameters

dev:the device
size:the number of characters to receive

Return values

  • the number of characters actually received
UART_HALF_DUPLEX_DEFAULT_TIMEOUT_US

Default recv timeout (in microseconds) 

1
(20000LU)
UART_HALF_DUPLEX_DIR_NONE

Don’t manage direction. 

1
{ NULL, NULL, NULL }
struct uart_half_duplex_dir_t

half-duplex UART direction management method type

void(* init()

function initializing direction management method

void(* enable_tx()

function enabling TX

void(* disable_tx()

function disabling TX

struct uart_half_duplex_params_t

Configuration for half-duplex UART.

uart.h::uart_t uart

the half-duplex UART bus to use

uint32_t baudrate

the baudrate to use

uart_half_duplex_dir_t dir

the direction management method

struct uart_half_duplex_t

Descriptor struct for half-duplex UART.

uint8_t * buffer

the buffer used for TX and RX

msp430_types.h::size_t size

the number of available elements for TX/RX

msp430_types.h::size_t buffer_max_size

the buffer size

uint32_t timeout_us

the maximum duration (in microseconds) for waiting data

uart_half_duplex_params_t params

the half-duplex UART configuration