RS232 / NMEA Output - VBOX 3iS Dual Antenna RTK
The RS232 output is present to provide a connection to a computer for configuring the settings of the VBOX 3iS through VBOX Setup software. It also can output NMEA format messages.
RS232 Racelogic Data Format
Protocol:
115200 Baud, no parity, 8 data bits, 1 stop bit
Message format:
$VB3isd$glbtttaaaaoooovvvhhAAAVVVDspprrSSHHPPRRyyxxYYzzddTTTkkqQQT1T1wwwWWWiicc
| Parameter | Number of bytes | Description |
|---|---|---|
|
$VB3isd$ |
7 |
Header |
|
g |
1 |
GPS sats Number of GPS satellites used |
|
l |
1 |
GLONASS sats Number of GLONASS satellites used |
|
b |
1 |
BeiDou sats Number of BeiDou satellites used |
|
ttt |
3 (MSB first) |
Time Ticks since midnight UTC, incrementing every 10 ms |
|
aaaa |
4 (MSB first) |
Latitude Signed integers, 0.0000001° per bit |
|
oooo |
4 (MSB first) |
Longitude Signed integers, 0.0000001° per bit |
|
vvv |
3 (MSB first) |
Velocity 0.001 km/h per bit |
|
hh |
2 (MSB first) |
Heading 0.01° per bit |
|
AAA |
3 (MSB first) |
Altitude 0.01 m per bit |
|
VVV |
3 (MSB first) |
Vertical velocity 0.001 m/s per bit |
| D | 1 | Dual Antenna Status |
|
s |
1 |
Solution type |
|
pp |
2 (MSB first) |
Pitch angle derived from KF 0.01° per bit |
|
rr |
2 (MSB first) |
Roll angle derived from KF 0.01° per bit |
| SS | 2 (MSB first) |
Slip angle derived from KF 0.01° per bit |
|
HH |
2 (MSB first) |
Heading derived from KF 0.01° per bit |
|
PP
|
2 (MSB first) |
Pitch rate derived from internal/external IMU 0.01°/sec per bit |
|
RR
|
2 (MSB first) |
Roll rate derived from internal/external IMU 0.01°/sec per bit |
|
yy |
2 (MSB first) |
Yaw rate derived from internal/external IMU 0.01°/sec per bit |
|
xx |
2 (MSB first) |
X accel from internal/external IMU 0.01 m/s² per bit |
|
YY |
2 (MSB first) |
Y accel from internal/external IMU 0.01 m/s² per bit |
|
zz |
2 (MSB first) |
Z accel from internal/external IMU 0.01 m/s² per bit |
|
dd |
2 (MSB first) |
Date DOS format |
|
TTT |
3 (MSB first) |
Trigger event time 0.000001 ms per bit |
|
kk |
2 (MSB first) |
Kalman Filter Status |
|
q |
1 |
Position Quality |
|
|
2 (MSB first) |
Speed Quality 0.001 m/s per bit |
|
T1T1 |
2 (MSB first) |
T1 0.0000001 ms per bit |
|
www |
3 (MSB first) |
Wheel speed 1 0.001 m/s per bit |
|
WWW |
3 (MSB first) |
Wheel speed 2 0.001 m/s per bit |
|
ii |
2 (MSB first) |
Heading_IMU2 derived from KF 0.01° per bit |
|
cc |
2 (MSB first) |
Checksum See CRC Calculation example below |
CRC Calculation example:
s[n] is a string containing the message
Polynomial:= 4129
CRC:=0;
for Loop:=1 to Length(s) do
begin
Temp:=s[Loop];
CRC:= CRC xor (integer(Temp) *256);
CRC:= CRC mod 65536;
for i:=7 downto 0 do
begin
if ( (CRC and 32768)=32768) then
begin
CRC:= CRC *2 ;
CRC:= CRC xor Polynomial;
end
else
begin
CRC:= CRC *2 ;
end;
CRC:=CRC mod 65536;
end;
end;
result:=CRC;
NMEA Output
The VBOX 3iS can output 7 types of NMEA messages:
- GGA
- GLL
- RMC
- VTG
- ZDA
- RLS
- ATT
NMEA - RLS
The contents of RLS are shown below:
$PTPSR,RLS,V,hhmmss.ss,IMUheading,IMUpitch,IMUroll,IMU3Dquality*cs
| Name | ASCII String | Units | Description | ||
|---|---|---|---|---|---|
| Format | Example | ||||
| $PTPSR | string | $PTPSR | Message ID | ||
| RLS | string | RLS | Sentence formatter | ||
| V | character | V | Whether the UTC time is valid | V=valid or N=not valid | |
| hhmmss.ss | hhmmss.ss | 114105.00 | UTC Time | Current time | |
| IMUheading | string | 157.531 | Degrees | Heading angle of IMU | |
| IMUpitch | string | 002.473 | Degrees | Pitch angle of IMU | |
| IMUroll | string | -02.635 | Degrees | Roll angle of IMU | |
| IMU3Dquality | string | 000.192 | 3D quality of IMU | ||
| cs | hexadecimal | *5F | Checksum | ||