Bosch Motorsport DDU 7, Руководство пользователя

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GPS sensor
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15 GPS sensor
15.1 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)
15.1.1 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: 9600 is standard for GPS, DDU 7 supports 1200…115200 baud. GPS Rx interface
baud rate must match DDU 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)
15.2 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.