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Wireless Sensor Network Middleware |
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/home/brennan/Software/sensix/source/C^4/corba/gov/lanl/isr/sensix/sensing/SerialGPS.java
Go to the documentation of this file.00001 00010 /* 00011 * Copyright 2008. Los Alamos National Security, LLC. This material 00012 * was produced under U.S. Government contract DE-AC52-06NA25396 for 00013 * Los Alamos National Laboratory (LANL), which is operated by Los 00014 * Alamos National Security, LLC, for the Department of Energy. The 00015 * U.S. Government has rights to use, reproduce, and distribute this 00016 * software. NEITHER THE GOVERNMENT NOR LOS ALAMOS NATIONAL SECURITY, 00017 * LLC, MAKES ANY WARRANTY, EXPRESS OR IMPLIED, OR ASSUMES ANY LEGAL 00018 * LIABILITY FOR THE USE OF THIS SOFTWARE. If software is modified to 00019 * produce derivative works, such modified software should be clearly 00020 * marked, so as not to confuse it with the version available from LANL. 00021 * 00022 * Additionally, this program is free software; you can redistribute 00023 * it and/or modify it under the terms of the GNU General Public 00024 * License as published by the Free Software Foundation; version 2 of 00025 * the License. Accordingly, this program is distributed in the hope 00026 * it will be useful, but WITHOUT ANY WARRANTY; without even the 00027 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 00028 * PURPOSE. See the GNU General Public License for more details. 00029 * 00030 * You should have received a copy of the GNU General Public License 00031 * along with this program; if not, write to the Free Software 00032 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 00033 */ 00034 00035 package gov.lanl.isr.sensix.sensing; 00036 00037 import gnu.io.*; 00038 import java.io.*; 00039 00040 00041 public class SerialGPS extends LocationImpl 00042 { 00043 private static final String CLASS_NAME = "gov.lanl.isr.sensix.SerialGPS"; 00044 00045 public static final int DEFAULT_BAUD = 38400; 00046 public static final char END_NMEA_LINE = ';'; 00047 public static final int MAX_RPT_ITVL = 100; // ms between acquisitions 00048 00049 private long previous_acq; 00050 private InputStreamReader data_in; 00051 private SerialPort sp; 00052 00053 00054 public SerialGPS(String serial_port) { 00055 this(serial_port, DEFAULT_BAUD); 00056 } 00057 00058 public SerialGPS(String serial_port, int speed) { 00059 super(); 00060 have_device = true; 00061 now = System.currentTimeMillis(); 00062 previous_acq = 0; 00063 try { 00064 CommPortIdentifier id = 00065 CommPortIdentifier.getPortIdentifier(serial_port); 00066 sp = (SerialPort)id.open(CLASS_NAME, 0); 00067 sp.setFlowControlMode(SerialPort.FLOWCONTROL_NONE); 00068 sp.disableReceiveFraming(); 00069 sp.setSerialPortParams(speed, SerialPort.DATABITS_8, 00070 SerialPort.STOPBITS_1, 00071 SerialPort.PARITY_NONE); 00072 data_in = new InputStreamReader(sp.getInputStream()); 00073 } catch (Exception e) { 00074 e.printStackTrace(System.err); 00075 // TODO throw something else 00076 } 00077 } 00078 00079 00080 00081 protected void getGPS() { 00082 long right_now = System.currentTimeMillis(); 00083 if ((previous_acq + MAX_RPT_ITVL) < right_now) { 00084 if (have_device) { 00085 String sentence = null; 00086 try { 00087 int input; 00088 while ((input = data_in.read()) != (int)END_NMEA_LINE) 00089 sentence += (char)input; 00090 sentence = sentence.substring(1, sentence.length() - 1); 00091 } catch(IOException e) { 00092 e.printStackTrace(System.err); 00093 return; 00094 } 00095 if (parseNMEA(sentence)) 00096 previous_acq = right_now; 00097 } 00098 else 00099 now = right_now; 00100 } 00101 } 00102 00103 private boolean parseNMEA(String nmea) { 00104 String time; 00105 String lat_deg, lat_min, lat_dir; 00106 String lon_deg, lon_min, lon_dir; 00107 String alt_str; 00108 boolean success = false; 00109 00110 int idx = nmea.indexOf(','); 00111 if (idx >= 0) { 00112 String prefix = nmea.substring(0, idx); 00113 if (prefix.equals("$GPGGA")) { 00114 nmea = nmea.substring(idx+1); 00115 00116 // time 00117 idx = nmea.indexOf(','); 00118 if (idx >= 0) { 00119 time = nmea.substring(0, idx); 00120 nmea = nmea.substring(idx+1); 00121 00122 // latitude 00123 idx = nmea.indexOf(','); 00124 if (idx >= 0) { 00125 lat_deg = nmea.substring(0, 2); 00126 lat_min = nmea.substring(2, idx); 00127 nmea = nmea.substring(idx+1); 00128 00129 idx = nmea.indexOf(','); 00130 if (idx >= 0) { 00131 lat_dir = nmea.substring(0, idx); 00132 nmea = nmea.substring(idx+1); 00133 00134 // longitude 00135 idx = nmea.indexOf(','); 00136 if (idx >= 0) { 00137 lon_deg = nmea.substring(0, 3); 00138 lon_min = nmea.substring(3, idx); 00139 nmea = nmea.substring(idx+1); 00140 00141 idx = nmea.indexOf(','); 00142 if (idx >= 0) { 00143 lon_dir = nmea.substring(0, idx); 00144 nmea = nmea.substring(idx+1); 00145 00146 // fix quality 00147 idx = nmea.indexOf(','); 00148 if (idx >= 0) { 00149 nmea = nmea.substring(idx+1); 00150 // number of satellites 00151 idx = nmea.indexOf(','); 00152 if (idx >= 0) { 00153 nmea = nmea.substring(idx+1); 00154 // horizontal dilution 00155 idx = nmea.indexOf(','); 00156 if (idx >= 0) { 00157 nmea = nmea.substring(idx+1); 00158 00159 // altitude 00160 idx = nmea.indexOf(','); 00161 if (idx >= 0) { 00162 alt_str = nmea.substring(0, idx); 00163 nmea = nmea.substring(idx+1); 00164 // ignore the rest 00165 00166 alt = Double.parseDouble(alt_str); 00167 00168 lon = Double.parseDouble(lon_deg); 00169 lon += Double.parseDouble(lon_min) / 60.0; 00170 if (lon_dir.equals("W")) 00171 lon *= -1.0; 00172 00173 lat = Double.parseDouble(lat_deg); 00174 lat += Double.parseDouble(lat_min) / 60.0; 00175 if (lat_dir.equals("S")) 00176 lat *= -1.0; 00177 00178 success = true; 00179 }}}}}}}}} 00180 } 00181 // TODO: other sentences 00182 } 00183 return success; 00184 } 00185 }