Marco Zecchini
/
Example_RTOS
Rtos API example
Diff: mbed-os/drivers/UARTSerial.h
- Revision:
- 0:9fca2b23d0ba
diff -r 000000000000 -r 9fca2b23d0ba mbed-os/drivers/UARTSerial.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-os/drivers/UARTSerial.h Sat Feb 23 12:13:36 2019 +0000 @@ -0,0 +1,264 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2017 ARM Limited + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef MBED_UARTSERIAL_H +#define MBED_UARTSERIAL_H + +#include "platform/platform.h" + +#if (DEVICE_SERIAL && DEVICE_INTERRUPTIN) || defined(DOXYGEN_ONLY) + +#include "FileHandle.h" +#include "SerialBase.h" +#include "InterruptIn.h" +#include "PlatformMutex.h" +#include "serial_api.h" +#include "CircularBuffer.h" +#include "platform/NonCopyable.h" + +#ifndef MBED_CONF_DRIVERS_UART_SERIAL_RXBUF_SIZE +#define MBED_CONF_DRIVERS_UART_SERIAL_RXBUF_SIZE 256 +#endif + +#ifndef MBED_CONF_DRIVERS_UART_SERIAL_TXBUF_SIZE +#define MBED_CONF_DRIVERS_UART_SERIAL_TXBUF_SIZE 256 +#endif + +namespace mbed { + +/** \addtogroup drivers */ + +/** Class providing buffered UART communication functionality using separate circular buffer for send and receive channels + * + * @ingroup drivers + */ + +class UARTSerial : private SerialBase, public FileHandle, private NonCopyable<UARTSerial> { + +public: + + /** Create a UARTSerial port, connected to the specified transmit and receive pins, with a particular baud rate. + * @param tx Transmit pin + * @param rx Receive pin + * @param baud The baud rate of the serial port (optional, defaults to MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE) + */ + UARTSerial(PinName tx, PinName rx, int baud = MBED_CONF_PLATFORM_DEFAULT_SERIAL_BAUD_RATE); + virtual ~UARTSerial(); + + /** Equivalent to POSIX poll(). Derived from FileHandle. + * Provides a mechanism to multiplex input/output over a set of file handles. + */ + virtual short poll(short events) const; + + /* Resolve ambiguities versus our private SerialBase + * (for writable, spelling differs, but just in case) + */ + using FileHandle::readable; + using FileHandle::writable; + + /** Write the contents of a buffer to a file + * + * @param buffer The buffer to write from + * @param length The number of bytes to write + * @return The number of bytes written, negative error on failure + */ + virtual ssize_t write(const void* buffer, size_t length); + + /** Read the contents of a file into a buffer + * + * Follows POSIX semantics: + * + * * if no data is available, and non-blocking set return -EAGAIN + * * if no data is available, and blocking set, wait until data is available + * * If any data is available, call returns immediately + * + * @param buffer The buffer to read in to + * @param length The number of bytes to read + * @return The number of bytes read, 0 at end of file, negative error on failure + */ + virtual ssize_t read(void* buffer, size_t length); + + /** Close a file + * + * @return 0 on success, negative error code on failure + */ + virtual int close(); + + /** Check if the file in an interactive terminal device + * + * @return True if the file is a terminal + * @return False if the file is not a terminal + * @return Negative error code on failure + */ + virtual int isatty(); + + /** Move the file position to a given offset from from a given location + * + * Not valid for a device type FileHandle like UARTSerial. + * In case of UARTSerial, returns ESPIPE + * + * @param offset The offset from whence to move to + * @param whence The start of where to seek + * SEEK_SET to start from beginning of file, + * SEEK_CUR to start from current position in file, + * SEEK_END to start from end of file + * @return The new offset of the file, negative error code on failure + */ + virtual off_t seek(off_t offset, int whence); + + /** Flush any buffers associated with the file + * + * @return 0 on success, negative error code on failure + */ + virtual int sync(); + + /** Set blocking or non-blocking mode + * The default is blocking. + * + * @param blocking true for blocking mode, false for non-blocking mode. + */ + virtual int set_blocking(bool blocking) + { + _blocking = blocking; + return 0; + } + + /** Register a callback on state change of the file. + * + * The specified callback will be called on state changes such as when + * the file can be written to or read from. + * + * The callback may be called in an interrupt context and should not + * perform expensive operations. + * + * Note! This is not intended as an attach-like asynchronous api, but rather + * as a building block for constructing such functionality. + * + * The exact timing of when the registered function + * is called is not guaranteed and susceptible to change. It should be used + * as a cue to make read/write/poll calls to find the current state. + * + * @param func Function to call on state change + */ + virtual void sigio(Callback<void()> func); + + /** Setup interrupt handler for DCD line + * + * If DCD line is connected, an IRQ handler will be setup. + * Does nothing if DCD is NC, i.e., not connected. + * + * @param dcd_pin Pin-name for DCD + * @param active_high a boolean set to true if DCD polarity is active low + */ + void set_data_carrier_detect(PinName dcd_pin, bool active_high = false); + + /** Set the baud rate + * + * @param baud The baud rate + */ + void set_baud(int baud); + + // Expose private SerialBase::Parity as UARTSerial::Parity + using SerialBase::Parity; + // In C++11, we wouldn't need to also have using directives for each value + using SerialBase::None; + using SerialBase::Odd; + using SerialBase::Even; + using SerialBase::Forced1; + using SerialBase::Forced0; + + /** Set the transmission format used by the serial port + * + * @param bits The number of bits in a word (5-8; default = 8) + * @param parity The parity used (None, Odd, Even, Forced1, Forced0; default = None) + * @param stop_bits The number of stop bits (1 or 2; default = 1) + */ + void set_format(int bits=8, Parity parity=UARTSerial::None, int stop_bits=1); + +#if DEVICE_SERIAL_FC + // For now use the base enum - but in future we may have extra options + // such as XON/XOFF or manual GPIO RTSCTS. + using SerialBase::Flow; + // In C++11, we wouldn't need to also have using directives for each value + using SerialBase::Disabled; + using SerialBase::RTS; + using SerialBase::CTS; + using SerialBase::RTSCTS; + + /** Set the flow control type on the serial port + * + * @param type the flow control type (Disabled, RTS, CTS, RTSCTS) + * @param flow1 the first flow control pin (RTS for RTS or RTSCTS, CTS for CTS) + * @param flow2 the second flow control pin (CTS for RTSCTS) + */ + void set_flow_control(Flow type, PinName flow1=NC, PinName flow2=NC); +#endif + +private: + + void wait_ms(uint32_t millisec); + + /** SerialBase lock override */ + virtual void lock(void); + + /** SerialBase unlock override */ + virtual void unlock(void); + + /** Acquire mutex */ + virtual void api_lock(void); + + /** Release mutex */ + virtual void api_unlock(void); + + /** Software serial buffers + * By default buffer size is 256 for TX and 256 for RX. Configurable through mbed_app.json + */ + CircularBuffer<char, MBED_CONF_DRIVERS_UART_SERIAL_RXBUF_SIZE> _rxbuf; + CircularBuffer<char, MBED_CONF_DRIVERS_UART_SERIAL_TXBUF_SIZE> _txbuf; + + PlatformMutex _mutex; + + Callback<void()> _sigio_cb; + + bool _blocking; + bool _tx_irq_enabled; + bool _rx_irq_enabled; + InterruptIn *_dcd_irq; + + /** Device Hanged up + * Determines if the device hanged up on us. + * + * @return True, if hanged up + */ + bool hup() const; + + /** ISRs for serial + * Routines to handle interrupts on serial pins. + * Copies data into Circular Buffer. + * Reports the state change to File handle. + */ + void tx_irq(void); + void rx_irq(void); + + void wake(void); + + void dcd_irq(void); + +}; +} //namespace mbed + +#endif //(DEVICE_SERIAL && DEVICE_INTERRUPTIN) || defined(DOXYGEN_ONLY) +#endif //MBED_UARTSERIAL_H