Development Data On/Off; Calculating Checksums For Nmea Input; Sirf Binary Protocol - RoyalTek REB-3000 Operational Manual

RoyalTek RGM-3000/REB-3000
GPS Module Operational Manual)
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Development Data On/Off

Use this command to enable development
data information if you can not get the
commands accepted. Invalid commands
generate debug information that enables the
user to determine the source of the
command rejection. Common reasons for
input command rejection are invalid
Table 16 Development Data On/Off Data Format
Name
Message ID
Debug
Checksum
<CR><LF>
Calculating Checksums for NMEA
Input
The Checksum is the 8-bit exclusive OR of all
the characters after $ and before *. (Not
including $ and *)

SiRF Binary Protocol

The serial communication protocol is designed
Start
Sequence
0xA0 1 ,
0xA2
0xYY denotes a hexadecimal byte value. 0xA0 equals 160.
Transport
The transport layer of the protocol
encapsulates a GPS message in two start
characters and two stop characters. The
values are chosen to be easily identifiable
and such that they are unlikely to occur
frequently in the data. In addition, the
transport layer prefixes the message with a
Clear Memory – Cold Start =1
Example Units
$PSRF105
1
*3E
Payload
Length Payload
Two-bytes Up to 2 10-1
(15-bits)
(<1023 )
checksum of parameter out of specified
range.
Table 16 contains the input values for the
following examples:
1. Debug On $PSRF105,1*3E
2. Debug Off $PSRF 105,0*3F
Description
PSRF105 protocol header
0=Off , 1= On
End of message termination
to include:
● Reliable transport of messages
● Ease of implementation
● Efficient implementation
● Independence from payload
Protocol Layers Transport Message
Message
Checksum
Two-bytes
(15-bits)
two-byte (15- bit)message length and a
two-byte(15-bit) choice of a 15-bit values for
length and check sum are designed such
that both message length and check sum
can not alias with either the stop of start
code.
Message Validation
The validation layer is of part of the transport,
19
EndSequence
0xB0,
0xB3