git.gag.com Git - fw/altos/blob - altosui/AltosTelemetryRecordRaw.java

   1 /*
   2  * Copyright © 2011 Keith Packard <keithp@keithp.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  16  */
  17
  18 package altosui;
  19
  20 import java.lang.*;
  21 import java.text.*;
  22 import java.util.HashMap;
  23
  24 public class AltosTelemetryRecordRaw implements AltosTelemetryRecord {
  25         int[]   bytes;
  26         int     serial;
  27         int     tick;
  28         int     type;
  29
  30         final static int packet_type_TM_sensor = 0x01;
  31         final static int packet_type_Tm_sensor = 0x02;
  32         final static int packet_type_Tn_sensor = 0x03;
  33         final static int packet_type_config = 0x04;
  34         final static int packet_type_GPS_location = 0x05;
  35         final static int packet_type_GPS_satellites = 0x06;
  36
  37         final static int PKT_APPEND_STATUS_1_CRC_OK             = (1 << 7);
  38         final static int PKT_APPEND_STATUS_1_LQI_MASK           = (0x7f);
  39         final static int PKT_APPEND_STATUS_1_LQI_SHIFT          = 0;
  40
  41         static boolean cksum(int[] bytes) {
  42                 int     sum = 0x5a;
  43                 for (int i = 1; i < bytes.length - 1; i++)
  44                         sum += bytes[i];
  45                 sum &= 0xff;
  46                 System.out.printf("%d bytes sum 0x%x last byte 0x%x\n",
  47                                   bytes.length, sum, bytes[bytes.length - 1]);
  48                 return sum == bytes[bytes.length - 1];
  49         }
  50
  51         public static AltosTelemetryRecord parse (String hex) throws ParseException, AltosCRCException {
  52                 AltosTelemetryRecord    r;
  53
  54                 int[] bytes;
  55                 try {
  56                         bytes = Altos.hexbytes(hex);
  57                 } catch (NumberFormatException ne) {
  58                         throw new ParseException(ne.getMessage(), 0);
  59                 }
  60
  61                 /* one for length, one for checksum */
  62                 if (bytes[0] != bytes.length - 2)
  63                         throw new ParseException(String.format("invalid length %d != %d\n",
  64                                                                bytes[0],
  65                                                                bytes.length - 2), 0);
  66                 if (!cksum(bytes))
  67                         throw new ParseException(String.format("invalid line \"%s\"", hex), 0);
  68
  69                 int     rssi = Altos.int8(bytes, bytes.length - 3) / 2 - 74;
  70                 int     status = Altos.uint8(bytes, bytes.length - 2);
  71
  72                 System.out.printf ("rssi 0x%x = %d status 0x%x\n",
  73                                    Altos.uint8(bytes, bytes.length - 3),
  74                                    rssi, status);
  75
  76                 if ((status & PKT_APPEND_STATUS_1_CRC_OK) == 0)
  77                         throw new AltosCRCException(rssi);
  78
  79                 /* length, data ..., rssi, status, checksum -- 4 bytes extra */
  80                 switch (bytes.length) {
  81                 case Altos.ao_telemetry_split_len + 4:
  82                         int     type = Altos.uint8(bytes, 4 + 1);
  83                         switch (type) {
  84                         case packet_type_TM_sensor:
  85                         case packet_type_Tm_sensor:
  86                         case packet_type_Tn_sensor:
  87                                 r = new AltosTelemetryRecordSensor(bytes);
  88                                 break;
  89                         default:
  90                                 r = new AltosTelemetryRecordRaw(bytes);
  91                                 break;
  92                         }
  93                 case Altos.ao_telemetry_legacy_len + 4:
  94                         r = new AltosTelemetryRecordLegacy(bytes, rssi, status);
  95                         break;
  96                 default:
  97                         throw new ParseException(String.format("Invalid packet length %d", bytes.length), 0);
  98                 }
  99                 return r;
 100         }
 101
 102         public int int8(int off) {
 103                 return Altos.int8(bytes, off + 1);
 104         }
 105
 106         public int uint8(int off) {
 107                 return Altos.uint8(bytes, off + 1);
 108         }
 109
 110         public int int16(int off) {
 111                 return Altos.int16(bytes, off + 1);
 112         }
 113
 114         public int uint16(int off) {
 115                 return Altos.uint16(bytes, off + 1);
 116         }
 117
 118         public int uint32(int off) {
 119                 return Altos.uint32(bytes, off + 1);
 120         }
 121
 122         public AltosTelemetryRecordRaw(int[] in_bytes) {
 123                 bytes = in_bytes;
 124                 serial = uint16(0);
 125                 tick   = uint16(2);
 126                 type   = uint8(4);
 127         }
 128
 129         public AltosRecord update_state(AltosRecord previous) {
 130                 if (previous != null)
 131                         return new AltosRecord(previous);
 132                 else
 133                         return new AltosRecord();
 134         }
 135 }