User's Manual

DRAFT TrimTrac Locator Technical Manual 31
Element Meaning
{x} Signifies that x can occur zero or more times
[x] Signifies that x may optionally occur once
Table 10, Basic Message Format
Message Framing
Each TrimTrac Application Protocol message is framed by the start, end ASCII
characters ‘>’, ‘<’, respectively. These characters are not allowed other than as
start-of-message and end-of-message indicators.
Message Qualifiers
A one-character Message Qualifier is used to describe the action to be taken on
the message. The following table lists the valid qualifiers:
Qualifier Action
Q Query for data or parameters (sent to TrimTrac
locator)
S Set or configure parameters (sent to TrimTrac locator)
R Response to a query or a scheduled or autonomous
report (from the TrimTrac locator)
Table 11, Message Qualifiers
Data String
The Message Qualifier and the Message Identifier dictate the format and length of
the data string. The Data String can consist of any printable ASCII characters with
the exception of the > and < characters. Most messages are length sensitive and
many use the ‘;’ character as field separator.
Security Password
A Security Password (PW) must be used in all communications with the TrimTrac
locator. The default Security Password is set to ‘00000000’; however, the
TrimTrac locator may be assigned any numeric password of up to eight characters
while the TrimTrac locator is connected to a provisioning module.
The TrimTrac locator checks all incoming messages for a Security Password and
all incoming message must include a Security Password. If the Security Password
included in a message sent to TrimTrac locator does not match the Security
Password configured in the TrimTrac Device, then the message is ignored.