N900 GPS Reverse Engineering

(what I learned so far)
Line 26: Line 26:
           S---------- DL----------------------
           S---------- DL----------------------
-
S = Static, unchanging normally
+
*S = Static, unchanging normally
-
MS = Mostly static, varying in value normally slightly
+
*MS = Mostly static, varying in value normally slightly
-
SS = Sometimes static, completely different values sometimes
+
*SS = Sometimes static, completely different values sometimes
-
I = Incrementing
+
*I = Incrementing
-
MI = Incrementing, but not every packet
+
*MI = Incrementing, but not every packet
-
D = Decrementing
+
*D = Decrementing
-
MD = Decrementing, but not every packet
+
*MD = Decrementing, but not every packet
-
TS = Time-sensitive; changes over (short) durations of time
+
*TS = Time-sensitive; changes over (short) durations of time
-
TL = Time-sensitive, longer duration
+
*TL = Time-sensitive, longer duration
-
T3 = "
+
*T3 = "
-
DS = Distance-sensitive; changes over at least 30m distance
+
*DS = Distance-sensitive; changes over at least 30m distance
-
DL = Distance-sensitive, like across the world; TEMP; *or* T4
+
*DL = Distance-sensitive, like across the world; TEMP; *or* T4
-
19,1a = 0000-e678 (hex)
+
*19,1a = 0000-e678 (hex)
-
20 =  
+
*20 =  
-
22,23 =  
+
*22,23 =  
-
28 =
+
*28 =
-
2b,2c = 0590-12a9 (hex)
+
*2b,2c = 0590-12a9 (hex)
-
2e,2f = eph (cm)
+
*2e,2f = eph (cm)
-
30 =
+
*30 =
-
35 =  
+
*35 =  
-
3c,3d = track: Direction of motion in hundredths of a degree
+
*3c,3d = track: Direction of motion in hundredths of a degree
-
3e,3f = epd: Track accuracy (in hundredths?)
+
*3e,3f = epd: Track accuracy (in hundredths?)
-
43 =
+
*43 =
-
45 =
+
*45 =

Revision as of 14:37, 21 July 2010

| 00000  00 92 01 00 00 00 00 xx  05 00 00 00 09 03 00 10
         S------------------- DL  S----------------------
| 00010  07 da 07 15 00 xx xx 00  xx xx 00 00 09 02 00 1c
         S------------- TL TS --        S----------------
| 00020  xx xx xx xx xx xx xx xx  00 00 xx xx 00 00 08 8b
         DL---       DL--- TS     S----       S---- ^eph^
| 00030  xx 00 xx xx xx xx xx xx  09 04 00 14 62 7e xx xx
            S- DL TS---    DL MS  S---------- track SS---
| 00040  xx xx 00 xx xx xx 00 xx  00 xx 00 00 09 05 00 74
         DL--- S-    TL    S- DS  S- DS S----------------
| 00050  09 00 00 00 00 02 xx xx  00 xx xx xx xx xx 00 00
         S---------------- DL MS  S- TS--- I  TS MI S----
| 00060  00 04 xx xx xx xx xx xx  xx xx 00 00 00 xx xx xx
         S---- T3 TS S- TL TS MS  TS MD S------- DL TS---
| 00070  00 xx xx xx xx xx 00 00  00 xx xx xx 00 03 xx xx
         S- TS--- I  TS MS S-------- T3 MS MS S---- TS MS
| 00080  xx xx 00 00 00 xx xx xx  00 xx xx xx xx xx 00 00
         TS MD S------- T3 TS MS  S- TS--- MS TS MI S----
| 00090  00 xx xx xx 00 03 xx xx  xx xx 00 00 00 xx xx xx
         S- TS------ S---- TS MD  TS MS S------- TS SS+TS
| 000a0  00 xx xx xx xx xx 00 00  00 xx xx xx 00 xx xx xx
         S- TL TS MS TS MD S-------- TS------ S- TL TS MI
| 000b0  xx xx 00 00 00 xx xx xx  00 xx xx xx xx xx 00 00
         TS--- S------- TS--- MS  S- TS--- MI TS MS S----
| 000c0  09 08 00 0c xx xx xx xx  xx xx xx xx
         S---------- DL----------------------
  • S = Static, unchanging normally
  • MS = Mostly static, varying in value normally slightly
  • SS = Sometimes static, completely different values sometimes
  • I = Incrementing
  • MI = Incrementing, but not every packet
  • D = Decrementing
  • MD = Decrementing, but not every packet
  • TS = Time-sensitive; changes over (short) durations of time
  • TL = Time-sensitive, longer duration
  • T3 = "
  • DS = Distance-sensitive; changes over at least 30m distance
  • DL = Distance-sensitive, like across the world; TEMP; *or* T4
  • 19,1a = 0000-e678 (hex)
  • 20 =
  • 22,23 =
  • 28 =
  • 2b,2c = 0590-12a9 (hex)
  • 2e,2f = eph (cm)
  • 30 =
  • 35 =
  • 3c,3d = track: Direction of motion in hundredths of a degree
  • 3e,3f = epd: Track accuracy (in hundredths?)
  • 43 =
  • 45 =