User`s guide

Chapter 3 - Receiver Descriptions
may be of the type that changes configuration parameters of the receiver. Examples of these
input command types include commands to change the initial position, receiver internal time and
date, satellite almanac, etc. These input commands, when received and validated by the receiver,
change the indicated parameter and result in a response message to show the new value of the
parameter that was changed. If the new value shows no change, then the input command was
either formatted improperly, or one of the input parameters was out of its valid range.
NOTE: Every change-parameter type input command (except
for the @@Ci message) has a corresponding response message
showing the configuration parameter change. To request the
current status of any current receiver parameter, simply enter an
input command with at least one parameter out of the normal range.
The response to properly formatted commands with out-of-range
parameters is to output the original unchanged value of the
parameter in the response message.
Input commands may also be of the type that enable or disable the output of data or status
messages. These output status messages include those that the external controller will use for
measuring position, velocity, and time. Status messages are output at the selected update rate
(typically, once per second) for those messages that contain position, velocity, or time, or can be
commanded to output the data one time upon request. The rate at which the data is output in the
continuous output mode is dependent on the update rate requested by the user. Table 3.7 below
shows the rates at which the data messages are output for each type of message, depending on
the setting of the continuous/polled option that is part of the input command.
Table 3.7: Binary Mode Data Message Output Rates
OUTPUT
MESSAGE TYPE
MESSAGE ID
CONTINUOUS
(m=1..255)
POLLED
(m=0)
12 Channel
Position/Status/Data
@@Ha
At user selected
update rate
When requested
ASCII Position
Message
@@Eq
At user selected
update rate
When requested
12 Channel T-RAIM
Status**
@@Hn
At user selected
update rate
When requested
Almanac Data @@Cb
When new almanac
data available
When requested
Visible Satellite
Status
@@Bb
When visibility status
changes
When requested
UTC Offset Status @@Bo
When UTC offset
available or when it
changes
When requested
Leap Second Status @@Gj When requested
**M12+ timing receiver only
In cases where more than one output message is scheduled during the same one second
interval, the receiver will output all scheduled messages but will attempt to limit the total number
of bytes transmitted each second to 800 bytes. For the case of multiple output messages, if the
Motorola GPS Products - M12+ User's Guide Revision 6.X 09FEB05
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