UM001
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4.2.3
Setup the Configuration Register
Once you have determined the desired outputs for your output messages, you will need to configure the
User Output Message Configuration Registers (Register 75 – 77). These registers are described in detail
under the Binary Output Register 1-3 in the System subsystem section, however for reference the format
of the register is shown below.
Binary Output Register 1-3
Register ID : 75-77
Access : Read / Write
Comment :
These registers allow the user to construct a custom output message that contains a
collection of desired estimated states and sensor measurements.
Size (Bytes): 6-22
Example Response: $VNWRG,75,2,4,1,8*XX
Offset
Name
Format
Unit
Description
0
AsyncMode
uint16
-
Selects whether the output message should be sent out on
the serial port(s) at a fixed rate.
0 = None. User message is not automatically sent out
either serial port.
1 = Message is sent out serial port 1 at a fixed rate.
2 = Message is sent out serial port 2 at a fixed rate.
3 = Message is sent out both serial ports at a fixed rate.
2
RateDivisor
uint16
-
Sets the fixed rate at which the message is sent out the
selected serial port(s). The number given is a divisor of the
ImuRate which is nominally 800Hz. For example to have
the sensor output at 50Hz you would set the Divisor equal
to 16.
4+N
OutputGroup(N)
uint8
-
Selects which output groups are active in the message.
The number of OutputFields in this message should equal
the number of active bits in the OutputGroup.
4+N+2*M
OutputField(1)
uint16
-
Selects which output data fields are active within the
selected output groups.
In the offset column above the variable N is the number of output group bytes. If data is requested
from only groups 1-7, there will be only one output group present (N=1). If data is requested from an
output group of 9-14, then two output groups bytes will be present.
The number of OutputFields present must be equal to the number of output groups selected in the
OutputGroup byte(s). For example if groups 1 and 3 are selected (OutputGroup = 0x05 or 0b00000101),
then there must be two OutputField parameters present (M = 2).
If the number of OutputFields is inconsistent with the number of OutputGroups selected, then the unit
will respond with an invalid parameter error when attempting to write to this register.
If the user attempts to turn on more data than it is possible to send out at the current baud rate, the
unit will resond with a insufficient baud rate error.
To turn off the binary output it is recommended to set the AsyncMode = 0.
