Vectornav VN-100, Руководство пользователя

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34 UM001
4.2.4 Example Case 1 – Selecting outputs from only the Common Group
For many applications you might be able to get by with only the output types available in the common
group. For these situations the configuration of the output message is simple. Suppose only the following
information shown below is desired.
Bit
Offset
Group 1
Common
0 TimeStartup
3 YawPitchRoll
5 AngularRate
For this example we will assume that the data will be polled using serial port 2 at 50 Hz.
To configure this output message you would send the following command to the VN-100.
$VNWRG,75,2,16,01,0029*XX
Now let’s dissect this command to see what is actually being set:
Field Value Description
Header $VN ASCII message header
Command WRG Write register command
Register ID 75 Register 75 (Config register for first output message)
AsyncMode 2 Message set to output on serial port 2.
RateDivisor 16 Divisor = 16. If the ImuRate = 800Hz then, the message output rate
will be (800 / 16 = 50 Hz).
OutputGroup 01 Groups = 0x01. (Binary group 1 enabled)
GroupField 1 0029 Group 1 Field = 0x0029. In binary 0x0029 = 0b00101001.
The active bits correspond to the following active output fields:
Bit 0 – TimeStartup
Bit 3 – YawPitchRoll
Bit 5 - AngularRate
Checksum XX Payload terminator and checksum. XX instructs the VN-100 to
bypass the checksum evaluation. This allows us to manually type
messages in a serial terminal without needing to calculate a valid
checksum.
End Line \r\n Carriage return and line feed. Terminates the ASCII message.
4.2.5 Example Case 2 – Outputs from multiple Output Groups without
extention bits
This example case demonstrates how to select multiple output fields from more than one output group.
Assume that the following bold output types are desired:
Bit
Offset
Group 1
Common
Group 3
IMU
Group 5
Attitude
0 TimeStartup
1
2 UncompAccel Quaternion
3 UncompAngularRate