modem.h

/*
    modem.h

    Copyright (c) 2014 seeed technology inc.
    Website    : www.seeed.cc
    Author     : lawliet zou
    Create Time: Feb 2014
    Change Log :

    The MIT License (MIT)

    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.
*/

#ifndef __MODEM_H__
#define __MODEM_H__

#include "arduino.h"
#include <SoftwareSerial.h>

#define DEFAULT_TIMEOUT     5

enum DataType {
    CMD     = 0,
    DATA    = 1,
};

/** Modem class.
    Used for Modem communication. attention that Modem module communicate with MCU in serial protocol
*/
class Modem {

  public:
    /** Create Modem Instance
        @param tx   uart transmit pin to communicate with Modem
        @param rx   uart receive pin to communicate with Modem
        @param baudRate baud rate of uart communication
    */
    Modem(int tx, int rx, int baudRate) : serialModem(tx, rx) {
        serialModem.begin(baudRate);
    };

  protected:
    /** Power on Modem
    */
    void preInit(void);

    /** check serialModem is readable or not
        @returns
            true on readable
            false on not readable
    */
    bool readable();

    /** read one byte from serialModem
        @returns
            one byte read from serialModem
    */
    char readByte(void);

    /** read from Modem module and save to buffer array
        @param  buffer  buffer array to save what read from Modem module
        @param  count   the maximal bytes number read from Modem module
        @param  timeOut time to wait for reading from Modem module
        @returns
            0 on success
            -1 on error
    */
    int readBuffer(char* buffer, int count, unsigned int timeOut);


    /** clean Buffer
        @param buffer   buffer to clean
        @param count    number of bytes to clean
    */
    void cleanBuffer(char* buffer, int count);

    /** send AT command to Modem module
        @param cmd  command array which will be send to GPRS module
    */
    void sendCmd(const char* cmd);

    /** send "AT" to Modem module
    */
    void sendATTest(void);

    /** compare the response from GPRS module with a string
        @param resp buffer to be compared
        @param len length that will be compared
        @param timeout  waiting seconds till timeout
    */
    bool respCmp(const char* resp, unsigned int len, unsigned int timeout);

    /** check Modem module response before time out
        @param  *resp   correct response which Modem module will return
        @param  *timeout    waiting seconds till timeout
        @returns
            0 on success
            -1 on error
    */
    int waitForResp(const char* resp, unsigned int timeout, DataType type);

    /** send AT command to GPRS module and wait for correct response
        @param  *cmd    AT command which will be send to GPRS module
        @param  *resp   correct response which GPRS module will return
        @param  *timeout    waiting seconds till timeout
        @returns
            0 on success
            -1 on error
    */
    int sendCmdAndWaitForResp(const char* data, const char* resp, unsigned timeout, DataType type);

    SoftwareSerial serialModem;
  private:

};

#endif