mbed official / mbed

The official Mbed 2 C/C++ SDK provides the software platform and libraries to build your applications.

Dependents:   hello SerialTestv11 SerialTestv12 Sierpinski ... more

mbed 2

This is the mbed 2 library. If you'd like to learn about Mbed OS please see the mbed-os docs.

drivers/UARTSerial.h@172:65be27845400, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 20:53:29 2019 +0000
Revision:
172:65be27845400
Parent:
171:3a7713b1edbc 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 156:ff21514d8981 1 /* mbed Microcontroller Library
AnnaBridge 156:ff21514d8981 2 * Copyright (c) 2006-2017 ARM Limited
AnnaBridge 172:65be27845400 3 * SPDX-License-Identifier: Apache-2.0
AnnaBridge 156:ff21514d8981 4 *
AnnaBridge 156:ff21514d8981 5 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 156:ff21514d8981 6 * you may not use this file except in compliance with the License.
AnnaBridge 156:ff21514d8981 7 * You may obtain a copy of the License at
AnnaBridge 156:ff21514d8981 8 *
AnnaBridge 156:ff21514d8981 9 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 156:ff21514d8981 10 *
AnnaBridge 156:ff21514d8981 11 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 156:ff21514d8981 12 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 156:ff21514d8981 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 156:ff21514d8981 14 * See the License for the specific language governing permissions and
AnnaBridge 156:ff21514d8981 15 * limitations under the License.
AnnaBridge 156:ff21514d8981 16 */
AnnaBridge 156:ff21514d8981 17
AnnaBridge 156:ff21514d8981 18 #ifndef MBED_UARTSERIAL_H
AnnaBridge 156:ff21514d8981 19 #define MBED_UARTSERIAL_H
AnnaBridge 156:ff21514d8981 20
AnnaBridge 156:ff21514d8981 21 #include "platform/platform.h"
AnnaBridge 156:ff21514d8981 22
AnnaBridge 156:ff21514d8981 23 #if (DEVICE_SERIAL && DEVICE_INTERRUPTIN) || defined(DOXYGEN_ONLY)
AnnaBridge 156:ff21514d8981 24
AnnaBridge 171:3a7713b1edbc 25 #include "platform/FileHandle.h"
AnnaBridge 156:ff21514d8981 26 #include "SerialBase.h"
AnnaBridge 156:ff21514d8981 27 #include "InterruptIn.h"
AnnaBridge 171:3a7713b1edbc 28 #include "platform/PlatformMutex.h"
AnnaBridge 171:3a7713b1edbc 29 #include "hal/serial_api.h"
AnnaBridge 171:3a7713b1edbc 30 #include "platform/CircularBuffer.h"
AnnaBridge 156:ff21514d8981 31 #include "platform/NonCopyable.h"
AnnaBridge 156:ff21514d8981 32
AnnaBridge 156:ff21514d8981 33 #ifndef MBED_CONF_DRIVERS_UART_SERIAL_RXBUF_SIZE
AnnaBridge 156:ff21514d8981 34 #define MBED_CONF_DRIVERS_UART_SERIAL_RXBUF_SIZE 256
AnnaBridge 156:ff21514d8981 35 #endif
AnnaBridge 156:ff21514d8981 36
AnnaBridge 156:ff21514d8981 37 #ifndef MBED_CONF_DRIVERS_UART_SERIAL_TXBUF_SIZE
AnnaBridge 156:ff21514d8981 38 #define MBED_CONF_DRIVERS_UART_SERIAL_TXBUF_SIZE 256
AnnaBridge 156:ff21514d8981 39 #endif
AnnaBridge 156:ff21514d8981 40
AnnaBridge 156:ff21514d8981 41 namespace mbed {
AnnaBridge 156:ff21514d8981 42
AnnaBridge 158:1c57384330a6 43 /** \addtogroup drivers */
AnnaBridge 158:1c57384330a6 44
AnnaBridge 158:1c57384330a6 45 /** Class providing buffered UART communication functionality using separate circular buffer for send and receive channels
AnnaBridge 170:e95d10626187 46 *
AnnaBridge 158:1c57384330a6 47 * @ingroup drivers
AnnaBridge 158:1c57384330a6 48 */
AnnaBridge 158:1c57384330a6 49
AnnaBridge 156:ff21514d8981 50 class UARTSerial : private SerialBase, public FileHandle, private NonCopyable<UARTSerial> {
AnnaBridge 156:ff21514d8981 51
AnnaBridge 156:ff21514d8981 52 public:
AnnaBridge 156:ff21514d8981 53
AnnaBridge 156:ff21514d8981 54 /** Create a UARTSerial port, connected to the specified transmit and receive pins, with a particular baud rate.
AnnaBridge 156:ff21514d8981 55 * @param tx Transmit pin
AnnaBridge 156:ff21514d8981 56 * @param rx Receive pin
AnnaBridge 156:ff21514d8981 57 * @param baud The baud rate of the serial port (optional, defaults to MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE)
AnnaBridge 156:ff21514d8981 58 */
AnnaBridge 156:ff21514d8981 59 UARTSerial(PinName tx, PinName rx, int baud = MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE);
AnnaBridge 156:ff21514d8981 60 virtual ~UARTSerial();
AnnaBridge 156:ff21514d8981 61
AnnaBridge 156:ff21514d8981 62 /** Equivalent to POSIX poll(). Derived from FileHandle.
AnnaBridge 156:ff21514d8981 63 * Provides a mechanism to multiplex input/output over a set of file handles.
AnnaBridge 156:ff21514d8981 64 */
AnnaBridge 156:ff21514d8981 65 virtual short poll(short events) const;
AnnaBridge 156:ff21514d8981 66
AnnaBridge 156:ff21514d8981 67 /* Resolve ambiguities versus our private SerialBase
AnnaBridge 156:ff21514d8981 68 * (for writable, spelling differs, but just in case)
AnnaBridge 156:ff21514d8981 69 */
AnnaBridge 156:ff21514d8981 70 using FileHandle::readable;
AnnaBridge 156:ff21514d8981 71 using FileHandle::writable;
AnnaBridge 156:ff21514d8981 72
AnnaBridge 156:ff21514d8981 73 /** Write the contents of a buffer to a file
AnnaBridge 156:ff21514d8981 74 *
Anna Bridge 160:5571c4ff569f 75 * Follows POSIX semantics:
Anna Bridge 160:5571c4ff569f 76 *
Anna Bridge 160:5571c4ff569f 77 * * if blocking, block until all data is written
Anna Bridge 160:5571c4ff569f 78 * * if no data can be written, and non-blocking set, return -EAGAIN
Anna Bridge 160:5571c4ff569f 79 * * if some data can be written, and non-blocking set, write partial
Anna Bridge 160:5571c4ff569f 80 *
AnnaBridge 156:ff21514d8981 81 * @param buffer The buffer to write from
AnnaBridge 156:ff21514d8981 82 * @param length The number of bytes to write
AnnaBridge 156:ff21514d8981 83 * @return The number of bytes written, negative error on failure
AnnaBridge 156:ff21514d8981 84 */
AnnaBridge 170:e95d10626187 85 virtual ssize_t write(const void *buffer, size_t length);
AnnaBridge 156:ff21514d8981 86
AnnaBridge 156:ff21514d8981 87 /** Read the contents of a file into a buffer
AnnaBridge 156:ff21514d8981 88 *
AnnaBridge 156:ff21514d8981 89 * Follows POSIX semantics:
AnnaBridge 156:ff21514d8981 90 *
AnnaBridge 156:ff21514d8981 91 * * if no data is available, and non-blocking set return -EAGAIN
AnnaBridge 156:ff21514d8981 92 * * if no data is available, and blocking set, wait until data is available
AnnaBridge 156:ff21514d8981 93 * * If any data is available, call returns immediately
AnnaBridge 156:ff21514d8981 94 *
AnnaBridge 156:ff21514d8981 95 * @param buffer The buffer to read in to
AnnaBridge 156:ff21514d8981 96 * @param length The number of bytes to read
AnnaBridge 156:ff21514d8981 97 * @return The number of bytes read, 0 at end of file, negative error on failure
AnnaBridge 156:ff21514d8981 98 */
AnnaBridge 170:e95d10626187 99 virtual ssize_t read(void *buffer, size_t length);
AnnaBridge 156:ff21514d8981 100
AnnaBridge 156:ff21514d8981 101 /** Close a file
AnnaBridge 156:ff21514d8981 102 *
AnnaBridge 156:ff21514d8981 103 * @return 0 on success, negative error code on failure
AnnaBridge 156:ff21514d8981 104 */
AnnaBridge 156:ff21514d8981 105 virtual int close();
AnnaBridge 156:ff21514d8981 106
AnnaBridge 156:ff21514d8981 107 /** Check if the file in an interactive terminal device
AnnaBridge 156:ff21514d8981 108 *
AnnaBridge 156:ff21514d8981 109 * @return True if the file is a terminal
AnnaBridge 156:ff21514d8981 110 * @return False if the file is not a terminal
AnnaBridge 156:ff21514d8981 111 * @return Negative error code on failure
AnnaBridge 156:ff21514d8981 112 */
AnnaBridge 156:ff21514d8981 113 virtual int isatty();
AnnaBridge 156:ff21514d8981 114
AnnaBridge 156:ff21514d8981 115 /** Move the file position to a given offset from from a given location
AnnaBridge 156:ff21514d8981 116 *
AnnaBridge 156:ff21514d8981 117 * Not valid for a device type FileHandle like UARTSerial.
AnnaBridge 156:ff21514d8981 118 * In case of UARTSerial, returns ESPIPE
AnnaBridge 156:ff21514d8981 119 *
AnnaBridge 156:ff21514d8981 120 * @param offset The offset from whence to move to
AnnaBridge 156:ff21514d8981 121 * @param whence The start of where to seek
AnnaBridge 156:ff21514d8981 122 * SEEK_SET to start from beginning of file,
AnnaBridge 156:ff21514d8981 123 * SEEK_CUR to start from current position in file,
AnnaBridge 156:ff21514d8981 124 * SEEK_END to start from end of file
AnnaBridge 156:ff21514d8981 125 * @return The new offset of the file, negative error code on failure
AnnaBridge 156:ff21514d8981 126 */
AnnaBridge 156:ff21514d8981 127 virtual off_t seek(off_t offset, int whence);
AnnaBridge 156:ff21514d8981 128
AnnaBridge 156:ff21514d8981 129 /** Flush any buffers associated with the file
AnnaBridge 156:ff21514d8981 130 *
AnnaBridge 156:ff21514d8981 131 * @return 0 on success, negative error code on failure
AnnaBridge 156:ff21514d8981 132 */
AnnaBridge 156:ff21514d8981 133 virtual int sync();
AnnaBridge 156:ff21514d8981 134
AnnaBridge 156:ff21514d8981 135 /** Set blocking or non-blocking mode
AnnaBridge 156:ff21514d8981 136 * The default is blocking.
AnnaBridge 156:ff21514d8981 137 *
AnnaBridge 156:ff21514d8981 138 * @param blocking true for blocking mode, false for non-blocking mode.
AnnaBridge 156:ff21514d8981 139 */
AnnaBridge 156:ff21514d8981 140 virtual int set_blocking(bool blocking)
AnnaBridge 156:ff21514d8981 141 {
AnnaBridge 156:ff21514d8981 142 _blocking = blocking;
AnnaBridge 156:ff21514d8981 143 return 0;
AnnaBridge 156:ff21514d8981 144 }
AnnaBridge 156:ff21514d8981 145
Anna Bridge 169:a7c7b631e539 146 /** Check current blocking or non-blocking mode for file operations.
Anna Bridge 169:a7c7b631e539 147 *
Anna Bridge 169:a7c7b631e539 148 * @return true for blocking mode, false for non-blocking mode.
Anna Bridge 169:a7c7b631e539 149 */
Anna Bridge 169:a7c7b631e539 150 virtual bool is_blocking() const
Anna Bridge 169:a7c7b631e539 151 {
Anna Bridge 169:a7c7b631e539 152 return _blocking;
Anna Bridge 169:a7c7b631e539 153 }
Anna Bridge 169:a7c7b631e539 154
AnnaBridge 156:ff21514d8981 155 /** Register a callback on state change of the file.
AnnaBridge 156:ff21514d8981 156 *
AnnaBridge 156:ff21514d8981 157 * The specified callback will be called on state changes such as when
AnnaBridge 156:ff21514d8981 158 * the file can be written to or read from.
AnnaBridge 156:ff21514d8981 159 *
AnnaBridge 156:ff21514d8981 160 * The callback may be called in an interrupt context and should not
AnnaBridge 156:ff21514d8981 161 * perform expensive operations.
AnnaBridge 156:ff21514d8981 162 *
AnnaBridge 156:ff21514d8981 163 * Note! This is not intended as an attach-like asynchronous api, but rather
AnnaBridge 156:ff21514d8981 164 * as a building block for constructing such functionality.
AnnaBridge 156:ff21514d8981 165 *
AnnaBridge 156:ff21514d8981 166 * The exact timing of when the registered function
AnnaBridge 156:ff21514d8981 167 * is called is not guaranteed and susceptible to change. It should be used
AnnaBridge 156:ff21514d8981 168 * as a cue to make read/write/poll calls to find the current state.
AnnaBridge 156:ff21514d8981 169 *
AnnaBridge 156:ff21514d8981 170 * @param func Function to call on state change
AnnaBridge 156:ff21514d8981 171 */
AnnaBridge 156:ff21514d8981 172 virtual void sigio(Callback<void()> func);
AnnaBridge 156:ff21514d8981 173
AnnaBridge 156:ff21514d8981 174 /** Setup interrupt handler for DCD line
AnnaBridge 156:ff21514d8981 175 *
AnnaBridge 156:ff21514d8981 176 * If DCD line is connected, an IRQ handler will be setup.
AnnaBridge 156:ff21514d8981 177 * Does nothing if DCD is NC, i.e., not connected.
AnnaBridge 156:ff21514d8981 178 *
AnnaBridge 156:ff21514d8981 179 * @param dcd_pin Pin-name for DCD
AnnaBridge 156:ff21514d8981 180 * @param active_high a boolean set to true if DCD polarity is active low
AnnaBridge 156:ff21514d8981 181 */
AnnaBridge 156:ff21514d8981 182 void set_data_carrier_detect(PinName dcd_pin, bool active_high = false);
AnnaBridge 156:ff21514d8981 183
AnnaBridge 156:ff21514d8981 184 /** Set the baud rate
AnnaBridge 156:ff21514d8981 185 *
AnnaBridge 156:ff21514d8981 186 * @param baud The baud rate
AnnaBridge 156:ff21514d8981 187 */
AnnaBridge 156:ff21514d8981 188 void set_baud(int baud);
AnnaBridge 156:ff21514d8981 189
Anna Bridge 160:5571c4ff569f 190 // Expose private SerialBase::Parity as UARTSerial::Parity
Anna Bridge 160:5571c4ff569f 191 using SerialBase::Parity;
Anna Bridge 160:5571c4ff569f 192 // In C++11, we wouldn't need to also have using directives for each value
Anna Bridge 160:5571c4ff569f 193 using SerialBase::None;
Anna Bridge 160:5571c4ff569f 194 using SerialBase::Odd;
Anna Bridge 160:5571c4ff569f 195 using SerialBase::Even;
Anna Bridge 160:5571c4ff569f 196 using SerialBase::Forced1;
Anna Bridge 160:5571c4ff569f 197 using SerialBase::Forced0;
Anna Bridge 160:5571c4ff569f 198
Anna Bridge 160:5571c4ff569f 199 /** Set the transmission format used by the serial port
Anna Bridge 160:5571c4ff569f 200 *
Anna Bridge 160:5571c4ff569f 201 * @param bits The number of bits in a word (5-8; default = 8)
Anna Bridge 160:5571c4ff569f 202 * @param parity The parity used (None, Odd, Even, Forced1, Forced0; default = None)
Anna Bridge 160:5571c4ff569f 203 * @param stop_bits The number of stop bits (1 or 2; default = 1)
Anna Bridge 160:5571c4ff569f 204 */
AnnaBridge 170:e95d10626187 205 void set_format(int bits = 8, Parity parity = UARTSerial::None, int stop_bits = 1);
Anna Bridge 160:5571c4ff569f 206
Anna Bridge 160:5571c4ff569f 207 #if DEVICE_SERIAL_FC
Anna Bridge 160:5571c4ff569f 208 // For now use the base enum - but in future we may have extra options
Anna Bridge 160:5571c4ff569f 209 // such as XON/XOFF or manual GPIO RTSCTS.
Anna Bridge 160:5571c4ff569f 210 using SerialBase::Flow;
Anna Bridge 160:5571c4ff569f 211 // In C++11, we wouldn't need to also have using directives for each value
Anna Bridge 160:5571c4ff569f 212 using SerialBase::Disabled;
Anna Bridge 160:5571c4ff569f 213 using SerialBase::RTS;
Anna Bridge 160:5571c4ff569f 214 using SerialBase::CTS;
Anna Bridge 160:5571c4ff569f 215 using SerialBase::RTSCTS;
Anna Bridge 160:5571c4ff569f 216
Anna Bridge 160:5571c4ff569f 217 /** Set the flow control type on the serial port
Anna Bridge 160:5571c4ff569f 218 *
Anna Bridge 160:5571c4ff569f 219 * @param type the flow control type (Disabled, RTS, CTS, RTSCTS)
Anna Bridge 160:5571c4ff569f 220 * @param flow1 the first flow control pin (RTS for RTS or RTSCTS, CTS for CTS)
Anna Bridge 160:5571c4ff569f 221 * @param flow2 the second flow control pin (CTS for RTSCTS)
Anna Bridge 160:5571c4ff569f 222 */
AnnaBridge 170:e95d10626187 223 void set_flow_control(Flow type, PinName flow1 = NC, PinName flow2 = NC);
Anna Bridge 160:5571c4ff569f 224 #endif
Anna Bridge 160:5571c4ff569f 225
AnnaBridge 156:ff21514d8981 226 private:
AnnaBridge 156:ff21514d8981 227
AnnaBridge 156:ff21514d8981 228 void wait_ms(uint32_t millisec);
AnnaBridge 156:ff21514d8981 229
AnnaBridge 156:ff21514d8981 230 /** SerialBase lock override */
AnnaBridge 156:ff21514d8981 231 virtual void lock(void);
AnnaBridge 156:ff21514d8981 232
AnnaBridge 156:ff21514d8981 233 /** SerialBase unlock override */
AnnaBridge 156:ff21514d8981 234 virtual void unlock(void);
AnnaBridge 156:ff21514d8981 235
AnnaBridge 156:ff21514d8981 236 /** Acquire mutex */
AnnaBridge 156:ff21514d8981 237 virtual void api_lock(void);
AnnaBridge 156:ff21514d8981 238
AnnaBridge 156:ff21514d8981 239 /** Release mutex */
AnnaBridge 156:ff21514d8981 240 virtual void api_unlock(void);
AnnaBridge 156:ff21514d8981 241
AnnaBridge 172:65be27845400 242 /** Unbuffered write - invoked when write called from critical section */
AnnaBridge 172:65be27845400 243 ssize_t write_unbuffered(const char *buf_ptr, size_t length);
AnnaBridge 172:65be27845400 244
AnnaBridge 156:ff21514d8981 245 /** Software serial buffers
AnnaBridge 156:ff21514d8981 246 * By default buffer size is 256 for TX and 256 for RX. Configurable through mbed_app.json
AnnaBridge 156:ff21514d8981 247 */
AnnaBridge 156:ff21514d8981 248 CircularBuffer<char, MBED_CONF_DRIVERS_UART_SERIAL_RXBUF_SIZE> _rxbuf;
AnnaBridge 156:ff21514d8981 249 CircularBuffer<char, MBED_CONF_DRIVERS_UART_SERIAL_TXBUF_SIZE> _txbuf;
AnnaBridge 156:ff21514d8981 250
AnnaBridge 156:ff21514d8981 251 PlatformMutex _mutex;
AnnaBridge 156:ff21514d8981 252
AnnaBridge 156:ff21514d8981 253 Callback<void()> _sigio_cb;
AnnaBridge 156:ff21514d8981 254
AnnaBridge 156:ff21514d8981 255 bool _blocking;
AnnaBridge 156:ff21514d8981 256 bool _tx_irq_enabled;
Anna Bridge 160:5571c4ff569f 257 bool _rx_irq_enabled;
AnnaBridge 156:ff21514d8981 258 InterruptIn *_dcd_irq;
AnnaBridge 156:ff21514d8981 259
AnnaBridge 156:ff21514d8981 260 /** Device Hanged up
AnnaBridge 156:ff21514d8981 261 * Determines if the device hanged up on us.
AnnaBridge 156:ff21514d8981 262 *
AnnaBridge 156:ff21514d8981 263 * @return True, if hanged up
AnnaBridge 156:ff21514d8981 264 */
AnnaBridge 156:ff21514d8981 265 bool hup() const;
AnnaBridge 156:ff21514d8981 266
AnnaBridge 156:ff21514d8981 267 /** ISRs for serial
AnnaBridge 156:ff21514d8981 268 * Routines to handle interrupts on serial pins.
AnnaBridge 156:ff21514d8981 269 * Copies data into Circular Buffer.
AnnaBridge 156:ff21514d8981 270 * Reports the state change to File handle.
AnnaBridge 156:ff21514d8981 271 */
AnnaBridge 156:ff21514d8981 272 void tx_irq(void);
AnnaBridge 156:ff21514d8981 273 void rx_irq(void);
AnnaBridge 156:ff21514d8981 274
AnnaBridge 156:ff21514d8981 275 void wake(void);
AnnaBridge 156:ff21514d8981 276
AnnaBridge 156:ff21514d8981 277 void dcd_irq(void);
AnnaBridge 156:ff21514d8981 278
AnnaBridge 156:ff21514d8981 279 };
AnnaBridge 156:ff21514d8981 280 } //namespace mbed
AnnaBridge 156:ff21514d8981 281
AnnaBridge 156:ff21514d8981 282 #endif //(DEVICE_SERIAL && DEVICE_INTERRUPTIN) || defined(DOXYGEN_ONLY)
AnnaBridge 156:ff21514d8981 283 #endif //MBED_UARTSERIAL_H