grovegprs: Initial implementation

This driver provides support for the Grove GPRS shield, V2:

http://www.seeedstudio.com/wiki/GPRS_Shield_V2.0

It provides a simple interface whereby a user can send and receive
commands and data from the device.  It is controlled by a standardized
set of "AT" commands.  A full description of these commands is
available here:

http://www.seeedstudio.com/wiki/images/7/72/AT_Commands_v1.11.pdf

Signed-off-by: Jon Trulson <jtrulson@ics.com>

examples/c++/CMakeLists.txt

@@ -138,6 +138,7 @@ add_executable (hyld9767-example hyld9767.cxx)
 add_executable (mg811-example mg811.cxx)
 add_executable (wheelencoder-example wheelencoder.cxx)
 add_executable (sm130-example sm130.cxx)
+add_executable (grovegprs-example grovegprs.cxx)
 
 include_directories (${PROJECT_SOURCE_DIR}/src/hmc5883l)
 include_directories (${PROJECT_SOURCE_DIR}/src/grove)
@@ -248,6 +249,7 @@ include_directories (${PROJECT_SOURCE_DIR}/src/hyld9767)
 include_directories (${PROJECT_SOURCE_DIR}/src/mg811)
 include_directories (${PROJECT_SOURCE_DIR}/src/wheelencoder)
 include_directories (${PROJECT_SOURCE_DIR}/src/sm130)
+include_directories (${PROJECT_SOURCE_DIR}/src/grovegprs)
 
 target_link_libraries (hmc5883l-example hmc5883l ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (groveled-example grove ${CMAKE_THREAD_LIBS_INIT})
@@ -387,3 +389,4 @@ target_link_libraries (hyld9767-example hyld9767 ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (mg811-example mg811 ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (wheelencoder-example wheelencoder ${CMAKE_THREAD_LIBS_INIT})
 target_link_libraries (sm130-example sm130 ${CMAKE_THREAD_LIBS_INIT})
+target_link_libraries (grovegprs-example grovegprs ${CMAKE_THREAD_LIBS_INIT})

examples/c++/grovegprs.cxx

@@ -0,0 +1,111 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * 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.
+ */
+
+#include <unistd.h>
+#include <iostream>
+#include <signal.h>
+#include <stdio.h>
+#include "grovegprs.h"
+
+using namespace std;
+using namespace upm;
+
+void printUsage(char *progname)
+{
+  cout << "Usage: " << progname << " [AT command]" << endl;
+  cout << endl;
+
+  cout << "If an argument is supplied on the command line, that argument is"
+       << endl;
+  cout << "sent to the module and the response is printed out." << endl;
+  cout << endl;
+  cout << "If no argument is used, then the manufacturer and the current" 
+       << endl;
+  cout << "saved profiles are queried and the results printed out." << endl;
+  cout << endl;
+  cout << endl;
+}
+
+// simple helper function to send a command and wait for a response
+void sendCommand(upm::GroveGPRS* sensor, string cmd)
+{
+  // commands need to be terminated with a carriage return
+  cmd += "\r";
+
+  sensor->writeDataStr(cmd);
+  
+  // wait up to 1 second
+  if (sensor->dataAvailable(1000))
+    {
+      cout << "Returned: " << sensor->readDataStr(1024) << endl;
+    }
+  else
+    {
+      cerr << "Timed out waiting for response" << endl;
+    }
+}
+
+
+int main(int argc, char **argv)
+{
+//! [Interesting]
+
+  // Instantiate a GroveGPRS Module on UART 0
+  upm::GroveGPRS* sensor = new upm::GroveGPRS(0);
+
+  // Set the baud rate, 19200 baud is the default.
+  if (sensor->setBaudRate(19200) != MRAA_SUCCESS)
+    {
+      cerr << "Failed to set tty baud rate" << endl;
+      return 1;
+    }
+
+  printUsage(argv[0]);
+
+  if (argc > 1)
+    {
+      cout << "Sending command line argument (" << argv[1] << ")..." << endl;
+      sendCommand(sensor, argv[1]);
+    }
+  else
+    {
+      // query the module manufacturer
+      cout << "Querying module manufacturer (AT+CGMI)..." << endl;
+      sendCommand(sensor, "AT+CGMI");
+
+      sleep(1);
+
+      // query the saved profiles
+      cout << "Querying the saved profiles (AT&V)..." << endl;
+      sendCommand(sensor, "AT&V");
+
+      // A comprehensive list is available from the datasheet at:
+      // http://www.seeedstudio.com/wiki/images/7/72/AT_Commands_v1.11.pdf
+    }
+
+//! [Interesting]
+
+  delete sensor;
+  return 0;
+}