UM001
35
4
MagNed
Also assume that you want the message to stream at 50 Hz over serial port 1.
To configure this output message you would send the following command to the VN-100.
$VNWRG,75,1,16,15,0001,000C,0014*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
1
Message sent on serial port 1.
RateDivisor
16
Divisor = 16. If the ImuRate = 800Hz then, the message output rate
will be (800 / 16 = 50 Hz).
OutputGroup
15
Groups = 0x15. In binary 0x15 = 0x00010101.
The active bits correspond to the following active output groups:
Bit 0 – Common
Bit 2 – Imu
Bit 4 - Attitude
GroupField 1
0001
Group 1 Field = 0x0001. In binary 0x0001 = 0b00000001.
The active bits correspond to the following active output fields:
Bit 0 – TimeStartup
GroupField 2
000C
Group 2 Field = 0x000C. In binary 0x000C = 0b00001100.
The active bits correspond to the following active output fields:
Bit 2 – UncompAccel
Bit 3 – UncompGyro
GroupField 3
0014
Group 3 Field = 0x0014. In binary 0x0014 = 0b00010100.
The active bits correspond to the following active output fields:
Bit 2 – Qtn
Bit 4 – MagNed
Checksum
XX
Payload terminator and checksum. XX instructs the VN-200 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.
