Bosch DDU 7, Руководство пользователя

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142 en | GPS Sensor Display Unit DDU 7
04.02.2019 | V 02 | Manual Bosch Motorsport
17 GPS Sensor
17.1 GPS (Global Positioning System)
Space-based global navigation satellite system
GPS provides positioning, navigation, and timing services to worldwide users
GPS receiver (sensor) gives digital information about position (longitude, latitude, height),
ground speed, course, and status
Two types of GPS receivers:
CAN output -> Read in messages via CAN Input of DDU 7 (not covered here)
Serial output -> Read in messages via RS232 Interface of DDU 7 (serial interface 2)
17.1.1 Serial interface characterization
Serial Interface is characterized by:
Voltage levels: RS232 is standard (+/-12 V), UART (0 V/ 5 V) needs level shifter
Baud rate: 9,600 is standard for GPS, DDU 7 supports 1,200 to 115,200 baud. GPS Rx
interface baud rate must match DDU 7 interface baud rate. DDU 7 Baud rate can be set with
the ‘GPS_BAUDRATE’ characteristic Data format: DDU 7 expects 8 data bits, no parity bit, 1
stop bit (8N1)
17.2 Protocol
DDU 7 expects NMEA Protocol (ASCII).
The following messages are decoded:
Message Function
GGA GPS fix information
GSA Overall satellite data
GSV Detailed satellite data
RMC Recommended minimum data for GPS
VTG Vector track and speed over the ground
On most GPS sensors, these messages are activated in the default configuration.
17.3 Sensor recommendation
The system has been tested with the Navilock NL-8004P MD6 Serial PPS Multi GNSS Receiver.
This sensor is based on a U-Blox 8 chipset and is fully configurable with the Navilock “U-
Center” software. To use this sensor with Bosch Motorsport components the transfer rate, the
satellite system and the update rate needs be reconfigured. More information about the
configuration can be found in the Appendix.
17.4 Measurement labels
The decoded NMEA messages are copied to these DDU 7 measurement labels.
Measurement label Function
gps_PDOP Position Dilution Of Precision
gps_HDOP Horizontal Dilution Of Precision
gps_VDOP Vertical Dilution Of Precision