SerialBase.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #ifndef MBED_SERIALBASE_H
00017 #define MBED_SERIALBASE_H
00018 
00019 #include "platform.h"
00020 
00021 #if DEVICE_SERIAL
00022 
00023 #include "Stream.h"
00024 #include "Callback.h"
00025 #include "serial_api.h"
00026 
00027 #if DEVICE_SERIAL_ASYNCH
00028 #include "CThunk.h"
00029 #include "dma_api.h"
00030 #endif
00031 
00032 namespace mbed {
00033 
00034 /** A base class for serial port implementations
00035  * Can't be instantiated directly (use Serial or RawSerial)
00036  *
00037  * @Note Synchronization level: Set by subclass
00038  */
00039 class SerialBase {
00040 
00041 public:
00042     /** Set the baud rate of the serial port
00043      *
00044      *  @param baudrate The baudrate of the serial port (default = 9600).
00045      */
00046     void baud(int baudrate);
00047 
00048     enum Parity {
00049         None = 0,
00050         Odd,
00051         Even,
00052         Forced1,
00053         Forced0
00054     };
00055 
00056     enum IrqType {
00057         RxIrq = 0,
00058         TxIrq
00059     };
00060 
00061     enum Flow {
00062         Disabled = 0,
00063         RTS,
00064         CTS,
00065         RTSCTS
00066     };
00067 
00068     /** Set the transmission format used by the serial port
00069      *
00070      *  @param bits The number of bits in a word (5-8; default = 8)
00071      *  @param parity The parity used (SerialBase::None, SerialBase::Odd, SerialBase::Even, SerialBase::Forced1, SerialBase::Forced0; default = SerialBase::None)
00072      *  @param stop The number of stop bits (1 or 2; default = 1)
00073      */
00074     void format(int bits=8, Parity parity=SerialBase::None, int stop_bits=1);
00075 
00076     /** Determine if there is a character available to read
00077      *
00078      *  @returns
00079      *    1 if there is a character available to read,
00080      *    0 otherwise
00081      */
00082     int readable();
00083 
00084     /** Determine if there is space available to write a character
00085      *
00086      *  @returns
00087      *    1 if there is space to write a character,
00088      *    0 otherwise
00089      */
00090     int writeable();
00091 
00092     /** Attach a function to call whenever a serial interrupt is generated
00093      *
00094      *  @param func A pointer to a void function, or 0 to set as none
00095      *  @param type Which serial interrupt to attach the member function to (Seriall::RxIrq for receive, TxIrq for transmit buffer empty)
00096      */
00097     void attach(Callback<void()> func, IrqType type=RxIrq);
00098 
00099     /** Attach a member function to call whenever a serial interrupt is generated
00100      *
00101      *  @param obj pointer to the object to call the member function on
00102      *  @param method pointer to the member function to be called
00103      *  @param type Which serial interrupt to attach the member function to (Seriall::RxIrq for receive, TxIrq for transmit buffer empty)
00104      */
00105     template<typename T>
00106     void attach(T *obj, void (T::*method)(), IrqType type=RxIrq) {
00107         attach(Callback<void()>(obj, method), type);
00108     }
00109 
00110     /** Attach a member function to call whenever a serial interrupt is generated
00111      *
00112      *  @param obj pointer to the object to call the member function on
00113      *  @param method pointer to the member function to be called
00114      *  @param type Which serial interrupt to attach the member function to (Seriall::RxIrq for receive, TxIrq for transmit buffer empty)
00115      */
00116     template<typename T>
00117     void attach(T *obj, void (*method)(T*), IrqType type=RxIrq) {
00118         attach(Callback<void()>(obj, method), type);
00119     }
00120 
00121     /** Generate a break condition on the serial line
00122      */
00123     void send_break();
00124 
00125 protected:
00126 
00127     /** Acquire exclusive access to this serial port
00128      */
00129     virtual void lock(void);
00130 
00131     /** Release exclusive access to this serial port
00132      */
00133     virtual void unlock(void);
00134 
00135 public:
00136 
00137 #if DEVICE_SERIAL_FC
00138     /** Set the flow control type on the serial port
00139      *
00140      *  @param type the flow control type (Disabled, RTS, CTS, RTSCTS)
00141      *  @param flow1 the first flow control pin (RTS for RTS or RTSCTS, CTS for CTS)
00142      *  @param flow2 the second flow control pin (CTS for RTSCTS)
00143      */
00144     void set_flow_control(Flow type, PinName flow1=NC, PinName flow2=NC);
00145 #endif
00146 
00147     static void _irq_handler(uint32_t id, SerialIrq irq_type);
00148 
00149 #if DEVICE_SERIAL_ASYNCH
00150 
00151     /** Begin asynchronous write using 8bit buffer. The completition invokes registered TX event callback
00152      *
00153      *  @param buffer   The buffer where received data will be stored
00154      *  @param length   The buffer length in bytes
00155      *  @param callback The event callback function
00156      *  @param event    The logical OR of TX events
00157      */
00158     int write(const uint8_t *buffer, int length, const event_callback_t& callback, int event = SERIAL_EVENT_TX_COMPLETE);
00159 
00160     /** Begin asynchronous write using 16bit buffer. The completition invokes registered TX event callback
00161      *
00162      *  @param buffer   The buffer where received data will be stored
00163      *  @param length   The buffer length in bytes
00164      *  @param callback The event callback function
00165      *  @param event    The logical OR of TX events
00166      */
00167     int write(const uint16_t *buffer, int length, const event_callback_t& callback, int event = SERIAL_EVENT_TX_COMPLETE);
00168 
00169     /** Abort the on-going write transfer
00170      */
00171     void abort_write();
00172 
00173     /** Begin asynchronous reading using 8bit buffer. The completition invokes registred RX event callback.
00174      *
00175      *  @param buffer     The buffer where received data will be stored
00176      *  @param length     The buffer length in bytes
00177      *  @param callback   The event callback function
00178      *  @param event      The logical OR of RX events
00179      *  @param char_match The matching character
00180      */
00181     int read(uint8_t *buffer, int length, const event_callback_t& callback, int event = SERIAL_EVENT_RX_COMPLETE, unsigned char char_match = SERIAL_RESERVED_CHAR_MATCH);
00182 
00183     /** Begin asynchronous reading using 16bit buffer. The completition invokes registred RX event callback.
00184      *
00185      *  @param buffer     The buffer where received data will be stored
00186      *  @param length     The buffer length in bytes
00187      *  @param callback   The event callback function
00188      *  @param event      The logical OR of RX events
00189      *  @param char_match The matching character
00190      */
00191     int read(uint16_t *buffer, int length, const event_callback_t& callback, int event = SERIAL_EVENT_RX_COMPLETE, unsigned char char_match = SERIAL_RESERVED_CHAR_MATCH);
00192 
00193     /** Abort the on-going read transfer
00194      */
00195     void abort_read();
00196 
00197     /** Configure DMA usage suggestion for non-blocking TX transfers
00198      *
00199      *  @param usage The usage DMA hint for peripheral
00200      *  @return Zero if the usage was set, -1 if a transaction is on-going
00201      */
00202     int set_dma_usage_tx(DMAUsage usage);
00203 
00204     /** Configure DMA usage suggestion for non-blocking RX transfers
00205      *
00206      *  @param usage The usage DMA hint for peripheral
00207      *  @return Zero if the usage was set, -1 if a transaction is on-going
00208      */
00209     int set_dma_usage_rx(DMAUsage usage);
00210 
00211 protected:
00212     void start_read(void *buffer, int buffer_size, char buffer_width, const event_callback_t& callback, int event, unsigned char char_match);
00213     void start_write(const void *buffer, int buffer_size, char buffer_width, const event_callback_t& callback, int event);
00214     void interrupt_handler_asynch(void);
00215 #endif
00216 
00217 protected:
00218     SerialBase(PinName tx, PinName rx);
00219     virtual ~SerialBase() {
00220     }
00221 
00222     int _base_getc();
00223     int _base_putc(int c);
00224 
00225 #if DEVICE_SERIAL_ASYNCH
00226     CThunk<SerialBase>  _thunk_irq;
00227     event_callback_t _tx_callback;
00228     event_callback_t _rx_callback;
00229     DMAUsage _tx_usage;
00230     DMAUsage _rx_usage;
00231 #endif
00232 
00233     serial_t         _serial;
00234     Callback<void()> _irq[2];
00235     int              _baud;
00236 
00237 };
00238 
00239 } // namespace mbed
00240 
00241 #endif
00242 
00243 #endif