aus APRS101.pdf:

dec ascii pos digi
28  0x1c   +   + Current Mic-E Data (Rev 0 beta)
29  0x1d   +   + Old Mic-E Data (Rev 0 beta)
33     !   +   + Position without timestamp (no APRS messaging), or Ultimeter 2000 WX Station
34     "         [Unused]
35     #   ?   + Peet Bros U-II Weather Station
36     $   +   + Raw GPS data or Ultimeter 2000 
37     %   ?   + Agrelo DFJr / MicroFinder
38     &   ?   + [Reserved   Map Feature]
39     '   +   + Old Mic-E Data (but Current data for TM-D700)
40     (         [Unused]
41     )   +   + Item
42     *   ?   + Peet Bros U-II Weather Station
43     +         [Reserved   Shelter data with time]
44     ,       - Invalid data or test data
45     -         [Unused]
46     .   ?   + [Reserved   Space weather]
47     /   +   + Position with timestamp (no APRS messaging)
48-57  0-9     - [Do not use]
58     :   -   + Message
59     ;   +   + Object
60     <   -   + Station Capabilities
61     =   +   + Position without timestamp (with APRS messaging)
62     >   -   - Status
63     ?   -   + Query
64     @   +   + Position with timestamp (with APRS messaging)
65-83  A-S     - [Do not use]
84     T   -   - Telemetry data
85-90  U-Z     - [Do not use]
91     [   +   + Maidenhead grid locator beacon (obsolete)
92     \         [Unused]
93     ]         [Unused]
94     ^         [Unused]
95     _   -   - Weather Report (without position)
96     `   +   + Current Mic-E Data (not used in TM-D700)
97-122 a-z     - [Do not use]
123    {   ?   + User-Defined APRS packet format
124    |       - [Do not use   TNC stream switch character]
125    }  +-   - Third-party traffic
126    ~       - [Do not use   TNC stream switch character]