Diff: SocketModem/io/MTSSerialFlowControl.h

Revision:

0:65004368569c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SocketModem/io/MTSSerialFlowControl.h	Tue Jul 01 21:31:54 2014 +0000
@@ -0,0 +1,81 @@
+/* Universal Socket Modem Interface Library
+* Copyright (c) 2013 Multi-Tech Systems
+*
+* 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 MTSSERIALFLOWCONTROL_H
+#define MTSSERIALFLOWCONTROL_H
+
+#include "mbed.h"
+#include "MTSSerial.h"
+
+
+namespace mts
+{
+
+/** This class derives from MTSBufferedIO/MTSSerial and provides a buffered wrapper to the
+* standard mbed Serial class along with generic RTS/CTS HW flow control. Since it
+* depends only on the mbed Serial, DigitalOut and InterruptIn classes for accessing
+* the serial data, this class is inherently portable accross different mbed platforms
+* and provides HW flow control even when not natively supported by the processors
+* serial port. If HW flow control is not needed, use MTSSerial instead. It should also
+* be noted that the RTS/CTS functionality in this class is implemented as a DTE device.
+*/
+class MTSSerialFlowControl : public MTSSerial
+{
+public:
+    /** Creates a new MTSSerialFlowControl object that can be used to talk to an mbed serial
+    * port through internal SW buffers. Note that this class also adds the ability to use
+    * RTS/CTS HW Flow Conrtol through and standard mbed DigitalIn and DigitalOut pins.
+    * The RTS and CTS functionality assumes this is a DTE device.
+    *
+    * @param TXD the transmit data pin on the desired mbed serial interface.
+    * @param RXD the receive data pin on the desired mbed serial interface.
+    * @param RTS the DigitalOut pin that RTS will be attached to. (DTE)
+    * @param CTS the DigitalIn pin that CTS will be attached to. (DTE)
+    * @param txBufferSize the size in bytes of the internal SW transmit buffer. The
+    * default is 64 bytes.
+    * @param rxBufferSize the size in bytes of the internal SW receive buffer. The
+    * default is 64 bytes.
+    * @param name an optional name for the serial port. The default is blank.
+    */
+    MTSSerialFlowControl(PinName TXD, PinName RXD, PinName RTS, PinName CTS, int txBufSize = 64, int rxBufSize = 64);
+
+    /** Destructs an MTSSerialFlowControl object and frees all related resources,
+    * including internal buffers.
+    */
+    ~MTSSerialFlowControl();
+    
+    /** This method clears all the data from the internal Rx or read buffer.
+    */
+    virtual void rxClear();
+
+private:
+    void notifyStartSending(); // Used to set cts start signal
+    void notifyStopSending(); // Used to set cts stop signal
+    
+    //This device acts as a DTE
+    bool rxReadyFlag;   //Tracks state change for rts signaling
+    DigitalOut rts; // Used to tell DCE to send or not send data
+    DigitalIn cts; // Used to check if DCE is ready for data
+    int highThreshold; // High water mark for setting cts to stop
+    int lowThreshold; // Low water mark for setting cts to start
+
+    virtual void handleRead(); // Method for handling data to be read
+    virtual void handleWrite(); // Method for handling data to be written
+};
+
+}
+
+#endif /* MTSSERIALFLOWCONTROL */