libUART
Easy to use library for accessing the UART (RS232) interface.
Functions:
uart_t *libUART_open(const char *dev, int baud, const char *opt);Open a UART port connection.
Arguments:
| Arg | Description |
|---|---|
| dev | The device name of the UART port |
| baud | The baud rate of the UART port (Use the enums in the header file, other values are not accepted) |
| opt | The configuration string of the UART port |
The configuration string must be 4 chars long. The first char represents the number of data bits (valid values are 5, 6, 7 or 8), the second char represents the parity (valid values are N for No parity, O for Odd parity or E for Even parity), the third char represents the number of stop bits (valid values are 1 or 2) and the fourth char represents the flow control (valid values are N for No flow control, S for Software flow control or H for Hardware flow control).
Example configuration string:
8N1N
| Char | Description |
|---|---|
| 8 | 8 data bits |
| N | No parity |
| 1 | 1 stop bit |
| N | No flow control |
Return:
On success, an uart_t object will be returned. On error, a NULL pointer will be returned.
void libUART_close(uart_t *uart);Close the connection.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
int libUART_send(uart_t *uart, char *send_buf, int len);Transmit data via UART.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| send_buf | The pointer to the data to transmit |
| len | The length of the data in bytes |
Return:
On success, the number of transmited bytes will be returned. On error, -1 will be returned.
int libUART_recv(uart_t *uart, char *recv_buf, int len);Receive data from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| recv_buf | The pointer where the received data is stored |
| len | The length of the data in bytes |
Return:
On success, the number of received bytes will be returned. On error, -1 will be returned.
int libUART_puts(uart_t *uart, char *msg);Transmit string via UART.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| msg | The string |
Return:
On success, the number of transmited bytes will be returned. On error, -1 will be returned.
int libUART_getc(uart_t *uart, char *c);Get character from UART.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| c | The returned character |
Return:
On success, the number of received bytes will be returned. On error, -1 will be returned.
int libUART_flush(uart_t *uart);Flush buffers.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_set_baud(uart_t *uart, int baud);Set the baud rate from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| baud | The baud rate (Use the enums in the header file, other values where not accepted) |
Return:
On success, 0 will be returned. On error, -1 will be returned.
libUART_get_baud(uart_t *uart, int *baud);Get the current baud rate from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| baud | The returned Baud Rate |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_fd(uart_t *uart, int *fd);Get the file descriptor from the UART port. (Linux/UNIX only)
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| fd | The returned File descriptor |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_handle(uart_t *uart, HANDLE *handle);Get the handle from the UART port. (Windows only)
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| handle | The returned HANDLE |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_dev(uart_t *uart, char **dev);Get the device of the from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| dev | The returned pointer to the device name. |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_set_databits(uart_t *uart, int data_bits);Set the data bits from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| data_bits | The number of data bits (valid values are 5, 6, 7 ot 8) |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_databits(uart_t *uart, int *data_bits);Get the data bits from the uart port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| data_bits | The returned Data Bits |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_set_parity(uart_t *uart, int parity);Set the parity from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| parity | The parity (valid values are UART_PARITY_NO, UART_PARITY_ODD or UART_PARITY_EVEN) |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_parity(uart_t *uart, int *parity);Get the parity from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| uart | The returned Parity |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_set_stopbits(uart_t *uart, int stop_bits);Set the stop bits from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| stop_bits | The number of stop bits (valid values are 1 or 2) |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_stopbits(uart_t *uart, int *stop_bits);Get the stop bits from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| stop_bits | The returned Stop Bits |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_set_flowctrl(uart_t *uart, int flow_ctrl);Set the flow control from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| flow_ctrl | The flow control (valid values are UART_FLOW_NO, UART_FLOW_SOFTWARE or UART_FLOW_HARDWARE) |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_flowctrl(uart_t *uart, int *flow_ctrl);Get the flow control from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| flow_ctrl | The returned Flow Control |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_set_pin(uart_t *uart, int pin, int state);Set the state of a specific pin from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| pin | The control pin of the UART |
| state | The state of the pin to set (valid values are 0 or 1) |
Pins:
| Pin | Description |
|---|---|
| UART_PIN_RTS | Request to Send |
| UART_PIN_CTS | Clear to Send |
| UART_PIN_DSR | Data Set Ready |
| UART_PIN_DCD | Data Carrier Detect |
| UART_PIN_DTR | Data Terminal Ready |
| UART_PIN_RI | Ring Indicator |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_pin(uart_t *uart, int pin, int *state);Get the state of a specific pin from the UART port.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| pin | The control pin of the UART |
| state | The returned State of the pin |
Return:
On success, 0 will be returned. On error, -1 will be returned.
int libUART_get_bytes_available(uart_t *uart, int *num);Get the current available bytes in the receive buffer.
Arguments:
| Arg | Description |
|---|---|
| uart | The uart_t object |
| num | The returned available bytes |
Return:
On success, 0 will be returned. On error, -1 will be returned.
void libUART_set_error(int enable);Enable or disable error message output (Default enabled).
char *libUART_get_libname(void);Get the library name.
char *libUART_get_libversion(void);Get the library version.
char *libUART_get_libcopyright(void);Get the library copyright.
LICENSE
Copyright (c) 2018-2020 Johannes Krottmayer
Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.