GPS Tracker for vehicle/car

2. Term and definition term,A.D. English meaning Chinese meaning CMPP China Mobile Peer to GPS Global Position

4.5.1       GPS information package

Format	Information content
	Date and Time	GPS information					Reserved extension bit
		GPS information length and satellites involved in locating	Latitude	Longitude	Speed	Course and status
Length (Byte)	6	1	4	4	1	2	N

4.5.1.1Date and time

Format	Year	Month	Day	Hour	Minute	Second
Length (Byte)	1	1	1	1	1	1

       For example 3:50:23 a.m. Mar 23rd 2010

       The value 0x0A 0x03 0x17 0x0F 0x32 0x17

4.5.1.2GPS information length,the number of the satellites involved in locating

1 byte converts to binary 8 bit, the first 4 bit means GPS info length, the late 4 bit means number of satellite involved in locating.

Note: The length includes 1 byte occupied by itself.

For example: 0x9C means GPS information length is 9 bytes, the number of satellite involved in locating is 12.

4.5.1.3Latitude

Occupy 4 bytes, representing the latitude value. Number range is from 0 to 162000000, which represents the range form 0°to 90°.Unit: 1/500 second

Conversion method:

A Convert the latitude (degrees, minutes) data from GPS module into a new form which represents the value only in minutes;

B Multiply the converted value by 30000, and then transform the result to hexadecimal number

For example22°32.7658′,(22×60+32.7658)×30000=40582974,then convert it to hexadecimal number 0x02 0x6B 0x3F 0x3E

4.5.1.4Longitude

Occupy 4 bytes, representing the longitude value of location data. Number ranges from 0 to 324000000, representing the range form 0°to 180°.Unit: 1/500 seconds, Conversion method is the same as latitude’s.

4.5.1.5Speed

Occupy 1 bytes, representing the speed of the device; ranges from 0 to 255,Unit: kilometer/hour.

4.5.1.6Status/Course

Occupy 2 bytes; representing the moving direction of the device; ranges from 0-360;

 If you are intested in our gps tracker products, please feel free to contact me any time.

GPS Tracker for vehicle/car