User`s guide

Chapter 5 - I/O Commands
OVERVIEW
Motorola binary commands can be used to initialize, configure, control and monitor the M12+
receivers. The binary commands are supported on the primary communications port at 9600
baud. Immediately following this page are listings of the input commands in alphabetical order.
Command and response structures are detailed on subsequent pages.
The input and output data fields following the message headers contain binary data that can be
interpreted as scaled floating point or integer data. The field width and appropriate scale factors
for each parameter are described in the individual I/O message format descriptions. Polarity of
floating point data is described via two's complement presentation.
Input commands may also be of the type query current parameter status, or enable and disable
the output of data or status messages. These output status messages include those that the
external controller will use for obtaining position, velocity, time, and status data.
Some care must be exercised in interpreting the command arguments. On the following pages it
sometimes makes sense to display the command arguments as ASCII characters, while in others
the hex representation may be a little clearer. As mentioned previously, the receiver doesn’t really
care which method is used to generate the messages sent to the receiver so long as the binary
strings sent to the receiver meet the specifications. Where possible, complete hex command
strings have been included as examples of what the complete command strings look like. Once a
basic understanding of the message protocols is developed by the user, things will become much
clearer.
Where applicable, information is provided comparing these commands and data structures to
their counterparts in older 8 channel Motorola receivers such as the GT+ and UT+ Oncore.
Also included in this chapter are message structures for the seven NMEA messages supported
by the M12+ positioning receiver (The NMEA protocol is not supported by the M12+ timing
receiver.
The WinOncore12 mnemonics shown in the following table are only to be used with the ‘Extra
Message’ window in WinOncore12. Each mnemonic causes WinOncore12 to run a macro that
sends a properly formatted string to the M12+ along with the checksum, carriage return, and line
feed. See the WinOncore12 help files for further explanation in the use of these commands.
Motorola GPS Products - M12+ User's Guide Revision 6.X 09FEB05
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