Data Sheet

UM7 DATASHEET
Rev. 1.6 – Released 1/10/2016
29
the * character preceding the checksum and the $ starting the packet. The
checksum computation does include commas in the packet.
Quaternion Packet - $PCHRQ
DESCRIPTION
The NMEA quaternion packet contains the attitude quaternion (valid when the sensor is in
quaternion mode).
PACKET FORMAT
$PCHRG,time,a,b,c,d,*checksum
e.g. $PCHRG,105.015,0.76592,0.76592,0.76592,0.76592,*60
PACKET FIELD DESCRIPTION
Field
Description
$PCHRQ
Header field, always precedes the quaternion packet
time
e.g. 105.015
This field can be up to 13 digits long. There will always be 3 decimal digits.
If no GPS is connected, this represents the amount of time in seconds since the
sensor was last turned on. If GPS with PPS is properly connected, this is
synchronized to UTC time of day.
a
e.g. 0.76592
This field can be up to 8 digits long. There will always be 5 decimal digits.
This represents element a of the attitude quaternion.
b
e.g. 0.76592
This field can be up to 8 digits long. There will always be 5 decimal digits.
This represents element b of the attitude quaternion.
c
e.g. 0.76592
This field can be up to 8 digits long. There will always be 5 decimal digits.
This represents element c of the attitude quaternion.
d
e.g. 0.76592
This field can be up to 8 digits long. There will always be 5 decimal digits.