1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
/*
* Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
* Contributions: Jon Trulson <jtrulson@ics.com>
* Brendan Le Foll <brendan.le.foll@intel.com>
* Copyright (c) 2014 - 2015 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#pragma once
/**
* @file
* @brief UART module
*
* UART is the Universal asynchronous receiver/transmitter interface to
* libmraa. It allows the exposure of UART pins on supported boards.
* With functionality to expand at a later date.
*
* @snippet uart.c Interesting
*/
#ifdef __cplusplus
extern "C" {
#endif
#include <stdio.h>
#include "common.h"
typedef struct _uart* mraa_uart_context;
/**
* Initialise uart_context, uses board mapping
*
* @param uart the index of the uart set to use
* @return uart context or NULL
*/
mraa_uart_context mraa_uart_init(int uart);
/**
* Initialise a raw uart_context. No board setup.
*
* @param path for example "/dev/ttyS0"
* @return uart context or NULL
*/
mraa_uart_context mraa_uart_init_raw(const char* path);
/**
* Flush the outbound data.
* Blocks until complete.
*
* @param dev The UART context
* @return Result of operation
*/
mraa_result_t mraa_uart_flush(mraa_uart_context dev);
/**
* Set the baudrate.
* Takes an int and will attempt to decide what baudrate is
* to be used on the UART hardware.
*
* @param dev The UART context
* @param baud unsigned int of baudrate i.e. 9600
* @return Result of operation
*/
mraa_result_t mraa_uart_set_baudrate(mraa_uart_context dev, unsigned int baud);
/**
* Set the transfer mode
* For example setting the mode to 8N1 would be
* "mraa_uart_set_mode(dev, 8,MRAA_UART_PARITY_NONE , 1)"
*
* @param dev The UART context
* @param bytesize data bits
* @param parity Parity bit setting
* @param stopbits stop bits
* @return Result of operation
*/
mraa_result_t mraa_uart_set_mode(mraa_uart_context dev, int bytesize, mraa_uart_parity_t parity, int stopbits);
/**
* Set the flowcontrol
*
* @param dev The UART context
* @param xonxoff XON/XOFF Software flow control.
* @param rtscts RTS/CTS out of band hardware flow control
* @return Result of operation
*/
mraa_result_t mraa_uart_set_flowcontrol(mraa_uart_context dev, mraa_boolean_t xonxoff, mraa_boolean_t rtscts);
/**
* Set the timeout for read and write operations
* <= 0 will disable that timeout
*
* @param dev The UART context
* @param read read timeout
* @param write write timeout
* @param interchar inbetween char timeout
* @return Result of operation
*/
mraa_result_t mraa_uart_set_timeout(mraa_uart_context dev, int read, int write, int interchar);
/**
* Get Char pointer with tty device path within Linux
* For example. Could point to "/dev/ttyS0"
*
* @param dev uart context
* @return char pointer of device path
*/
const char* mraa_uart_get_dev_path(mraa_uart_context dev);
/**
* Destroy a mraa_uart_context
*
* @param dev uart context
* @return mraa_result_t
*/
mraa_result_t mraa_uart_stop(mraa_uart_context dev);
/**
* Read bytes from the device into a buffer
*
* @param dev uart context
* @param buf buffer pointer
* @param length maximum size of buffer
* @return the number of bytes read, or -1 if an error occurred
*/
int mraa_uart_read(mraa_uart_context dev, char* buf, size_t length);
/**
* Write bytes in buffer to a device
*
* @param dev uart context
* @param buf buffer pointer
* @param length maximum size of buffer
* @return the number of bytes written, or -1 if an error occurred
*/
int mraa_uart_write(mraa_uart_context dev, const char* buf, size_t length);
/**
* Check to see if data is available on the device for reading
*
* @param dev uart context
* @param millis number of milliseconds to wait, or 0 to return immediately
* @return 1 if there is data available to read, 0 otherwise
*/
mraa_boolean_t mraa_uart_data_available(mraa_uart_context dev, unsigned int millis);
#ifdef __cplusplus
}
#endif
|
